The U.S. Department of Justice (DoJ) on Tuesday announced the seizure of a domain associated with a bulletproof hosting provider (BPH) named Virtualine.
The move was in response to the service being used to commit and facilitate prolific criminal activity, including “the advertisement of sexually explicit images of minors, the intentional disclosure of nonconsensual intimate visual depictions
Japan’s GMO Internet Group is offering up to $1 million in total for tips that help catch the attackers who breached its Onamae.com Desktop Cloud service, after refusing to pay an extortion demand.
The reward program opened on October 28 and pays only if a tip helps lead to an arrest or an international wanted notice. The service hosts Windows desktops used for FX trading,
Tailscale has released version 1.104.4 to fix flaws in its built-in SSH server that could let an attacker reach services and files on other servers that only the root user should be able to touch.
The flaws are in how Tailscale SSH forwards network connections, a job the Tailscale background process carries out with root privileges. To use them, an attacker must
The critical Oracle PeopleSoft bug that ShinyHunters has exploited since May is not one flaw but three chained together, the researchers who reported it said this week.
Oracle patched all three under a single identifier, CVE-2026-35273, in June. Its root is a server-side request forgery (SSRF) that reaches an internal management interface because PeopleSoft trusts its own loopback address
Interpol’s annual Operation Serengeti, now in its third iteration, led to 1,462 arrests across 20 African countries and the US, recovering $105 million in stolen funds.
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Tuesday added two vulnerabilities impacting Adobe Commerce and Magento, and Google’s Brotli decoder library to its Known Exploited Vulnerabilities (KEV) catalog, citing evidence of active exploitation.
The vulnerabilities are listed below –
CVE-2026-111497 (CVSS score: 9.2) – An unchecked return value vulnerability in
Cron and its spares. Clear root’s crontab in one go, so the restore and watchdog lines are removed. Then kill any running zen2, devnull2, or serv processes; killed earlier, the watchdog restarts them within a minute. Remove the k.php beacons (/var/lib/asterisk/bin/zen2, devnull2, zen222, devnull312, devnull212, /tmp/.cache/update, /dev/shm/.systemd/kernel). Unlock (chattr -i, -a) and delete the eight crontab backups: /usr/lib/.systemd/.cache, /usr/share/.fonts/.config, /var/lib/.dbus/.data, /var/tmp/.X11/.Xauthority, /opt/.local/.bashrc, /var/cache/.fontconfig/.cfg, /etc/.ssl/.cert, and /root/.config/.pref.
Login and boot triggers. Remove the base64 stager from /root/.bash_profile, /root/.bashrc, and /etc/rc.local.
Accounts and SSH. Remove every extra UID-0 account and any account whose /etc/shadow hash begins with $1$nRz1Cbtk$ (legitimate service accounts with that hash need new passwords, not deletion). Restore sshd_config, where root login was re-enabled.
Web application. Remove the 12 webshell copies, the .htaccess, the freepbxusers row in ampusers, and /var/www/html/admin/modules/freepbx_ha/license.php.
Credentials. Only now rotate the secrets in the 17 files and across every account on the host.
Conclusion
The hard part of the campaign used to be getting the implant off the box, and that has not changed. What has changed is that the box is no longer the whole problem: an organization that rebuilds but does not rotate has removed the operator’s calling platform and handed over its carrier account.
The code ties this generation to the actor in our May report through the takeover script, backdoor hash, and staging host, and a gate rotated in step across JOMANGY and ZenharR.
The operator is now rotating exactly the strings defenders were given, so detections built on provenance and behavior will outlast this build, and detections built on its hashes will not. CRIL continues to monitor INJ3CTOR3’s infrastructure.
Indicators of Compromise
Hashes and strings rotate between builds; use them to confirm a finding, not as your only detection.
Network: outbound HTTP POSTs from a PBX to any /hima_data/ path or to either staging host. A PBX seldom needs outbound web access beyond vendor updates, so egress allow-listing closes this channel.
Carrier: alert on trunk registrations from outside your own IP ranges, and on premium or international destinations, off-hours calling, and unusual concurrency. Set spend caps and destination blocks where your carrier offers them.
For Law Enforcement Agencies and CERTs
By design, victims’ credentials were collected on the two staging hosts, which stopped responding in late September 2026. Going offline does not end exposure: hosting providers may still retain server data, and infected PBXs keep trying to upload their credentials every minute to addresses that could be reassigned to someone else.
Both are reasons for law enforcement and national CERTs, which have the legal standing that researchers lack, to work with the providers on preserving that data and sinkholing the addresses, which would also identify victims for notification. We saw the uploads in code; we did not capture one in transit and hold no victim list.
Two Staging Hosts, Split by Encoding
An infected host now talks to both staging hosts, and which one depends on whether the command was written in plain text or base64. The /x takeover script is byte-identical on both.
Reference
Encoding
Points to
k.php line 2 (re-runs /x), eight cron schedules in /x, wr.php’s callback
Plain text
160[.]119[.]69[.]4
Camouflaged cron payloads, login-triggered stager
Base64
45[.]95[.]147[.]178
Credential upload
Base64
Both
In April, all of these pointed to 45[.]95[.]147[.]178. We assess that the operator replaced the address in plain text and never re-encoded the base64 strings; the credential upload, which names both hosts, appears deliberate. This host is distinct from the scanner 160[.]119[.]76[.]250, which is named in our May report.
Defend: block both hosts in both directions, and decode every base64-encoded string in a crontab or shell profile before deciding which hosts a host talks to. A plain-text review would miss every channel that still reaches 45[.]95[.]147[.]178.
The Webshell: Same Program, New Identifiers
Decoded, the September JOMANGY panel is identical to April’s except for the values defenders were told to look for.
Per-build watermark. Our May report advised hunting for trace_e1ebf9066a951be519a24140711839ea, present in every April copy. The September builds carry trace_bd42a8a0d23ae16c85dede7d2abaec05 (45[.]95[.]147[.]178) and trace_7544725ebaaadac217dfaa7ca8e8fe7e (160[.]119[.]69[.]4), so that hunt now misses current infections.
One gate for two generations. JOMANGY and ZenharR share a single hardcoded MD5 gate hash, rotated together from a2f6863413c4192a4abfa360577b9961 to 8b3a1d970fda0c17a0b785a990fb7b6a. Our May report listed the April value under ZenharR only.
A forged administrator session. Behind the gate, the FreePBX button builds an admin session using FreePBX’s own ampuser class and setAdmin(); in our lab, it opened the full console without any password. Therefore, changing the FreePBX admin password affects neither the gate nor this session. (See Figure 3 below)
Figure 3: The panel’s Freepbx and Elastix buttons forge an admin session without a password
Because each of these identifiers changes between builds, the detection approach later in this report focuses on who put a file on disk rather than on what the file contains.
The .htaccess Door and the Access-Log Gap
k.php writes a seven-line .htaccess to /var/www/html/admin/views/. It does not hide the webshell; it unblocks it, and it lets requests reach a copy without naming it.
Simulating an operator and a victim in an isolated environment, we confirmed that a request to a URL containing an encoded space returned a working webshell for the attacker. The access log records only the requested path, never the file that answered, so searching logs for the webshell byits filename can return nothing on a host that is serving it.
Defend: check every .htaccess across the web root for who put it there; one that no package, FreePBX module, or member of your team accounts for is suspect, whatever it contains. Because the takeover script wipes logs, treat log hunting as secondary: requests with %20, %09, or %0A directly after a slash that return 200 are worth a look where logs survive.
What the FreePBX Console Won’t Show You
FreePBX lists the trunks it created from its own database; Asterisk reads whatever is in its configuration files. In our lab, a trunk we wrote directly into /etc/asterisk/pjsip_custom.conf carried a call while the FreePBX Trunks page reported no records (See Figure 4 below). We did not see the campaign plant one, but its root-equivalent accounts and stolen trunk secrets give the operator everything needed to do so.
Figure 4: Our lab trunk, known to Asterisk and carrying calls, invisible in the FreePBX console
Defend: audit from the Asterisk CLI (pjsip show endpoints, pjsip show registrations, sip show peers, sip show registry) and compare with what the console lists. Review the *_custom.conf files for trunks or contexts that nobody on your team added.
What Keeps It There
Before detecting or cleaning, it helps to see the whole apparatus. Everything in Figure 5 is read from /x and k.php: ways the implant stays on the box, and doors allowing the operator to come back, through a system account or a single web request. Each piece can rebuild/repair all others under a minute, which is why removing any one of them on its own fails. (See Figure 5 below)
Figure 5: Persistence channels that rebuild each other, and the backdoors they stay open
Detecting It Without IOCs
The operator rotates hashes, watermarks, gate values, and hosts between builds, so asking whether a file is known-bad quickly stops working. The better question is who put the file there: compare what is on disk with what the package manager or a clean install says it should be.
On the host: triage with beagle.sh
PBX admins can run beagle.sh, a report-only script that makes no changes to the host, to check a PBX server for signs of compromise. (See Figure 6 below)
Check
What it flags
Packed shells
Several identical, same-size PHP files across unrelated directories
Locked files
chattr +i or +a under the web root or in hidden directories
Unowned .htaccess
An .htaccess no installed package accounts for
Self-rebuilding cron
A cron line that downloads a file and hands it to a shell
Accounts
An extra UID-0 account, or a full-permission FreePBX admin, nobody created
Blocklist
Addresses dropped in and out by iptables outside fail2ban’s chains
Figure 6: beagle.sh (Source: 0x1da5 GitHub)
The script separated one infected server from one clean server of the same FreePBX version, a sample of one, so expect some legitimate findings. However, it cannot tell you whether the credentials have already been left: that happens during the first cron run, within a minute of infection, and long before anyone scans. The upload leaves no file behind, and the takeover script wipes what might have recorded it: the web server, Asterisk, cron and audit logs, plus shell and MySQL histories, which makes forensic timelines hard to reconstruct.
With telemetry
The most distinctive actions leave little on disk; in our detonation, backdoor accounts were created and deleted 27 seconds apart. These eleven behaviors are detection strategies to build into your own tooling:
Layer
Behavior
What it catches
Host
crond spawns a shell that downloads a file and runs it
The takeover script on its single run, before persistence and before credentials leave
Host
The web server account spawns a shell
The webshell’s command box in use
Host
A cron child rewrites the crontab every minute without reading it first
Beacon reinstallation
Host
chattr +i or touch -r on a file in the web root
The lock and the borrowed timestamp
Host
Twelve PHP files were written to the web root in the same second
The webshell copies, as they are written; fan-out
Network
The PBX contacts staging host roughly every 60 seconds
The beacon’s rhythm, whatever the address
Network
Many configuration files read, then outbound POST requests
Credentials leaving
Web
A request with leading encoded whitespace returns 200 for a path not on disk
The .htaccess door
Decoy
Any read of a decoy config file that the implant reads, but nothing legitimate does
Credential collection, with no false positives by design
Phone
Channels originate over AMI or the CLI outside your dial plan
A call asking for nothing legitimate
Phone
CDRs with premium destinations, off-hours calling and unusual concurrency
The fraud itself
The last two catch the fraud rather than the machinery, whatever the files are called, and whether you ever find the shell. The host rows need process telemetry that PBX appliances rarely have, which is part of why so many stay infected.
Why Cleanup Fails, and the Order That Works
First move
Why it fails on its own
Delete the webshell
Cron re-runs k.php within minutes and rewrites all 12 copies, the .htaccess, and the immutable flags.
Patch FreePBX
Sangoma’s advisory for CVE-2025-57819 states the fix prevents new exploitation but does not clean a compromised system.
Change the admin password
The gate and the forged session never use it, and the backdoor accounts bypass the FreePBX login.
Shadowserver data showed more than 900 compromised FreePBX instances in February 2026; over 700 of them were still compromised in May. Rebuilding from a clean image is the most reliable fix; if you clean in place, work from the system layer up, because it replants everything above it.
Preserve first
The takeover script truncates logs, then deletes them, and clears shell and database history, so evidence shrinks with every run:
Cut the host off from the internet, or at least block all outbound traffic except to your SIP carrier. Blocking only the two known staging hosts is not enough if the operator has moved. With no route out, the minute-by-minute downloads fail, and nothing more is uploaded. One local loop survives: a watchdog cron line re-runs the cached copy of k.php at /var/lib/asterisk/bin/zen2 every minute, rebuilding the webshells offline, which is why cron comes first in the cleanup below.
Capture all crontabs and the eight backups listed below, /etc/passwd, /etc/shadow, shell profiles, and the web root with lsattr output and change times.
Export the FreePBX ampusers table, the call records database, and the Asterisk full log, and ask your carrier to preserve CDRs and registration logs.
Then clean, in this order
Cron and its spares. Clear root’s crontab in one go, so the restore and watchdog lines are removed. Then kill any running zen2, devnull2, or serv processes; killed earlier, the watchdog restarts them within a minute. Remove the k.php beacons (/var/lib/asterisk/bin/zen2, devnull2, zen222, devnull312, devnull212, /tmp/.cache/update, /dev/shm/.systemd/kernel). Unlock (chattr -i, -a) and delete the eight crontab backups: /usr/lib/.systemd/.cache, /usr/share/.fonts/.config, /var/lib/.dbus/.data, /var/tmp/.X11/.Xauthority, /opt/.local/.bashrc, /var/cache/.fontconfig/.cfg, /etc/.ssl/.cert, and /root/.config/.pref.
Login and boot triggers. Remove the base64 stager from /root/.bash_profile, /root/.bashrc, and /etc/rc.local.
Accounts and SSH. Remove every extra UID-0 account and any account whose /etc/shadow hash begins with $1$nRz1Cbtk$ (legitimate service accounts with that hash need new passwords, not deletion). Restore sshd_config, where root login was re-enabled.
Web application. Remove the 12 webshell copies, the .htaccess, the freepbxusers row in ampusers, and /var/www/html/admin/modules/freepbx_ha/license.php.
Credentials. Only now rotate the secrets in the 17 files and across every account on the host.
Conclusion
The hard part of the campaign used to be getting the implant off the box, and that has not changed. What has changed is that the box is no longer the whole problem: an organization that rebuilds but does not rotate has removed the operator’s calling platform and handed over its carrier account.
The code ties this generation to the actor in our May report through the takeover script, backdoor hash, and staging host, and a gate rotated in step across JOMANGY and ZenharR.
The operator is now rotating exactly the strings defenders were given, so detections built on provenance and behavior will outlast this build, and detections built on its hashes will not. CRIL continues to monitor INJ3CTOR3’s infrastructure.
Indicators of Compromise
Hashes and strings rotate between builds; use them to confirm a finding, not as your only detection.
Credentials leave on every run. k.php uploads 17 configuration files to both staging hosts every minute the host stays infected.
The fraud no longer needs your PBX. A stolen trunk secret lets the operator register and place calls as you from anywhere.
Last report’s identifiers have expired. Each build now carries its own watermark, and the webshell gate hash was rotated.
Two staging hosts. Plain-text commands now point to 160[.]119[.]69[.]4, while base64-encoded ones still use 45[.]95[.]147[.]178.
Clean-looking logs and consoles prove nothing. Requests through an encoded space reach the shell without being named in the access log, and trunks are written directly to /etc/asterisk; they do not appear in the FreePBX console.
The Campaign So Far
INJ3CTOR3 has been abusing Asterisk-based phone systems for toll fraud since at least 2020. Check Point Research named the operation that November, when it exploited CVE-2019-19006 in FreePBX and used a basic webshell to read amportal.conf and sip_additional.conf by hand. Unit 42 reported a related operation against Elastix in 2022, Fortinet documented the EncystPHP webshell in January 2026, and our May report covered JOMANGY.
The playbook has held for six years: scan for exposed PBXs, exploit or brute-force a way in, plant a password-gated webshell, and dial out at the victim’s expense. Figure 1 below shows the chain as it stands in the September build, now including the credential upload back to the staging hosts.
Figure 1: INJ3CTOR3 attack chain, September generation. (Source: 0x1da5 GitHub)
What Changed Since Our Last Report
We compared the April artifacts behind our May report with the 9 September collection from both staging hosts, after decoding every layer.
Unchanged: the decoded webshell panel, the encoding chain (base64 in the shell script, base64 again in PHP, then ROT13), the persistence channels, the backdoor account password hash, and the borrowed timestamp. Behavioral detections built on our May report still apply.
Credential Exfiltration: The Implant Is No Longer the Product
The September k.php ends with two new base64-encoded lines, each holding 17 curl commands that upload one configuration file apiece to /hima_data/index.php, one line per staging host (See Figure 2 below). The paths are typed out by hand and cover FreePBX, Issabel, and Elastix layouts. The collector path echoes hima, a backdoor account the takeover script creates. The name goes back further: Check Point’s 2020 INJ3CTOR3 report shows a Telegram post by a user called Hima sharing a tool that scans and cracks SIP ranges, saving its output as HimaResults.
Figure 2: k.php line 34, decoded into 17 file uploads
Three of the cron beacons fetch and run k.php every minute (the others every two or three minutes), so the upload repeats every minute during the infection. Rotating credentials on a still-infected host hands the new secrets to the operator within minutes.
The database password (AMPDBPASS), the MySQL root password, and any AMI password stored there
Outbound mail
/etc/postfix/sasl_passwd
The SMTP relay account, with your mail provider
This opens a second route to fraud. Our May report covered calls placed through the webshell, which require the shell to be alive and to land in the victim’s own call records. With a stolen trunk secret, the operator can register to the carrier from any machine and call as the victim, leaving nothing on the host, unless the carrier also restricts the trunk to the victim’s IP addresses. A successful disinfection stops the first route; only rotation stops the second.
Detection
Network: outbound HTTP POSTs from a PBX to any /hima_data/ path or to either staging host. A PBX seldom needs outbound web access beyond vendor updates, so egress allow-listing closes this channel.
Carrier: alert on trunk registrations from outside your own IP ranges, and on premium or international destinations, off-hours calling, and unusual concurrency. Set spend caps and destination blocks where your carrier offers them.
For Law Enforcement Agencies and CERTs
By design, victims’ credentials were collected on the two staging hosts, which stopped responding in late September 2026. Going offline does not end exposure: hosting providers may still retain server data, and infected PBXs keep trying to upload their credentials every minute to addresses that could be reassigned to someone else.
Both are reasons for law enforcement and national CERTs, which have the legal standing that researchers lack, to work with the providers on preserving that data and sinkholing the addresses, which would also identify victims for notification. We saw the uploads in code; we did not capture one in transit and hold no victim list.
Two Staging Hosts, Split by Encoding
An infected host now talks to both staging hosts, and which one depends on whether the command was written in plain text or base64. The /x takeover script is byte-identical on both.
Reference
Encoding
Points to
k.php line 2 (re-runs /x), eight cron schedules in /x, wr.php’s callback
Plain text
160[.]119[.]69[.]4
Camouflaged cron payloads, login-triggered stager
Base64
45[.]95[.]147[.]178
Credential upload
Base64
Both
In April, all of these pointed to 45[.]95[.]147[.]178. We assess that the operator replaced the address in plain text and never re-encoded the base64 strings; the credential upload, which names both hosts, appears deliberate. This host is distinct from the scanner 160[.]119[.]76[.]250, which is named in our May report.
Defend: block both hosts in both directions, and decode every base64-encoded string in a crontab or shell profile before deciding which hosts a host talks to. A plain-text review would miss every channel that still reaches 45[.]95[.]147[.]178.
The Webshell: Same Program, New Identifiers
Decoded, the September JOMANGY panel is identical to April’s except for the values defenders were told to look for.
Per-build watermark. Our May report advised hunting for trace_e1ebf9066a951be519a24140711839ea, present in every April copy. The September builds carry trace_bd42a8a0d23ae16c85dede7d2abaec05 (45[.]95[.]147[.]178) and trace_7544725ebaaadac217dfaa7ca8e8fe7e (160[.]119[.]69[.]4), so that hunt now misses current infections.
One gate for two generations. JOMANGY and ZenharR share a single hardcoded MD5 gate hash, rotated together from a2f6863413c4192a4abfa360577b9961 to 8b3a1d970fda0c17a0b785a990fb7b6a. Our May report listed the April value under ZenharR only.
A forged administrator session. Behind the gate, the FreePBX button builds an admin session using FreePBX’s own ampuser class and setAdmin(); in our lab, it opened the full console without any password. Therefore, changing the FreePBX admin password affects neither the gate nor this session. (See Figure 3 below)
Figure 3: The panel’s Freepbx and Elastix buttons forge an admin session without a password
Because each of these identifiers changes between builds, the detection approach later in this report focuses on who put a file on disk rather than on what the file contains.
The .htaccess Door and the Access-Log Gap
k.php writes a seven-line .htaccess to /var/www/html/admin/views/. It does not hide the webshell; it unblocks it, and it lets requests reach a copy without naming it.
Simulating an operator and a victim in an isolated environment, we confirmed that a request to a URL containing an encoded space returned a working webshell for the attacker. The access log records only the requested path, never the file that answered, so searching logs for the webshell byits filename can return nothing on a host that is serving it.
Defend: check every .htaccess across the web root for who put it there; one that no package, FreePBX module, or member of your team accounts for is suspect, whatever it contains. Because the takeover script wipes logs, treat log hunting as secondary: requests with %20, %09, or %0A directly after a slash that return 200 are worth a look where logs survive.
What the FreePBX Console Won’t Show You
FreePBX lists the trunks it created from its own database; Asterisk reads whatever is in its configuration files. In our lab, a trunk we wrote directly into /etc/asterisk/pjsip_custom.conf carried a call while the FreePBX Trunks page reported no records (See Figure 4 below). We did not see the campaign plant one, but its root-equivalent accounts and stolen trunk secrets give the operator everything needed to do so.
Figure 4: Our lab trunk, known to Asterisk and carrying calls, invisible in the FreePBX console
Defend: audit from the Asterisk CLI (pjsip show endpoints, pjsip show registrations, sip show peers, sip show registry) and compare with what the console lists. Review the *_custom.conf files for trunks or contexts that nobody on your team added.
What Keeps It There
Before detecting or cleaning, it helps to see the whole apparatus. Everything in Figure 5 is read from /x and k.php: ways the implant stays on the box, and doors allowing the operator to come back, through a system account or a single web request. Each piece can rebuild/repair all others under a minute, which is why removing any one of them on its own fails. (See Figure 5 below)
Figure 5: Persistence channels that rebuild each other, and the backdoors they stay open
Detecting It Without IOCs
The operator rotates hashes, watermarks, gate values, and hosts between builds, so asking whether a file is known-bad quickly stops working. The better question is who put the file there: compare what is on disk with what the package manager or a clean install says it should be.
On the host: triage with beagle.sh
PBX admins can run beagle.sh, a report-only script that makes no changes to the host, to check a PBX server for signs of compromise. (See Figure 6 below)
Check
What it flags
Packed shells
Several identical, same-size PHP files across unrelated directories
Locked files
chattr +i or +a under the web root or in hidden directories
Unowned .htaccess
An .htaccess no installed package accounts for
Self-rebuilding cron
A cron line that downloads a file and hands it to a shell
Accounts
An extra UID-0 account, or a full-permission FreePBX admin, nobody created
Blocklist
Addresses dropped in and out by iptables outside fail2ban’s chains
Figure 6: beagle.sh (Source: 0x1da5 GitHub)
The script separated one infected server from one clean server of the same FreePBX version, a sample of one, so expect some legitimate findings. However, it cannot tell you whether the credentials have already been left: that happens during the first cron run, within a minute of infection, and long before anyone scans. The upload leaves no file behind, and the takeover script wipes what might have recorded it: the web server, Asterisk, cron and audit logs, plus shell and MySQL histories, which makes forensic timelines hard to reconstruct.
With telemetry
The most distinctive actions leave little on disk; in our detonation, backdoor accounts were created and deleted 27 seconds apart. These eleven behaviors are detection strategies to build into your own tooling:
Layer
Behavior
What it catches
Host
crond spawns a shell that downloads a file and runs it
The takeover script on its single run, before persistence and before credentials leave
Host
The web server account spawns a shell
The webshell’s command box in use
Host
A cron child rewrites the crontab every minute without reading it first
Beacon reinstallation
Host
chattr +i or touch -r on a file in the web root
The lock and the borrowed timestamp
Host
Twelve PHP files were written to the web root in the same second
The webshell copies, as they are written; fan-out
Network
The PBX contacts staging host roughly every 60 seconds
The beacon’s rhythm, whatever the address
Network
Many configuration files read, then outbound POST requests
Credentials leaving
Web
A request with leading encoded whitespace returns 200 for a path not on disk
The .htaccess door
Decoy
Any read of a decoy config file that the implant reads, but nothing legitimate does
Credential collection, with no false positives by design
Phone
Channels originate over AMI or the CLI outside your dial plan
A call asking for nothing legitimate
Phone
CDRs with premium destinations, off-hours calling and unusual concurrency
The fraud itself
The last two catch the fraud rather than the machinery, whatever the files are called, and whether you ever find the shell. The host rows need process telemetry that PBX appliances rarely have, which is part of why so many stay infected.
Why Cleanup Fails, and the Order That Works
First move
Why it fails on its own
Delete the webshell
Cron re-runs k.php within minutes and rewrites all 12 copies, the .htaccess, and the immutable flags.
Patch FreePBX
Sangoma’s advisory for CVE-2025-57819 states the fix prevents new exploitation but does not clean a compromised system.
Change the admin password
The gate and the forged session never use it, and the backdoor accounts bypass the FreePBX login.
Shadowserver data showed more than 900 compromised FreePBX instances in February 2026; over 700 of them were still compromised in May. Rebuilding from a clean image is the most reliable fix; if you clean in place, work from the system layer up, because it replants everything above it.
Preserve first
The takeover script truncates logs, then deletes them, and clears shell and database history, so evidence shrinks with every run:
Cut the host off from the internet, or at least block all outbound traffic except to your SIP carrier. Blocking only the two known staging hosts is not enough if the operator has moved. With no route out, the minute-by-minute downloads fail, and nothing more is uploaded. One local loop survives: a watchdog cron line re-runs the cached copy of k.php at /var/lib/asterisk/bin/zen2 every minute, rebuilding the webshells offline, which is why cron comes first in the cleanup below.
Capture all crontabs and the eight backups listed below, /etc/passwd, /etc/shadow, shell profiles, and the web root with lsattr output and change times.
Export the FreePBX ampusers table, the call records database, and the Asterisk full log, and ask your carrier to preserve CDRs and registration logs.
Then clean, in this order
Cron and its spares. Clear root’s crontab in one go, so the restore and watchdog lines are removed. Then kill any running zen2, devnull2, or serv processes; killed earlier, the watchdog restarts them within a minute. Remove the k.php beacons (/var/lib/asterisk/bin/zen2, devnull2, zen222, devnull312, devnull212, /tmp/.cache/update, /dev/shm/.systemd/kernel). Unlock (chattr -i, -a) and delete the eight crontab backups: /usr/lib/.systemd/.cache, /usr/share/.fonts/.config, /var/lib/.dbus/.data, /var/tmp/.X11/.Xauthority, /opt/.local/.bashrc, /var/cache/.fontconfig/.cfg, /etc/.ssl/.cert, and /root/.config/.pref.
Login and boot triggers. Remove the base64 stager from /root/.bash_profile, /root/.bashrc, and /etc/rc.local.
Accounts and SSH. Remove every extra UID-0 account and any account whose /etc/shadow hash begins with $1$nRz1Cbtk$ (legitimate service accounts with that hash need new passwords, not deletion). Restore sshd_config, where root login was re-enabled.
Web application. Remove the 12 webshell copies, the .htaccess, the freepbxusers row in ampusers, and /var/www/html/admin/modules/freepbx_ha/license.php.
Credentials. Only now rotate the secrets in the 17 files and across every account on the host.
Conclusion
The hard part of the campaign used to be getting the implant off the box, and that has not changed. What has changed is that the box is no longer the whole problem: an organization that rebuilds but does not rotate has removed the operator’s calling platform and handed over its carrier account.
The code ties this generation to the actor in our May report through the takeover script, backdoor hash, and staging host, and a gate rotated in step across JOMANGY and ZenharR.
The operator is now rotating exactly the strings defenders were given, so detections built on provenance and behavior will outlast this build, and detections built on its hashes will not. CRIL continues to monitor INJ3CTOR3’s infrastructure.
Indicators of Compromise
Hashes and strings rotate between builds; use them to confirm a finding, not as your only detection.
In May, Cyble Research & Intelligence Labs (CRIL) documented JOMANGY, a PHP webshell generation deployed by INJ3CTOR3 with self-healing persistence channels and a built-in toll-fraud dialer.
Back then, the fraud ran through the victim’s own PBX, so removing the implant would have stopped it. Artifacts we collected from the operator’s C2 staging servers during mid-September 2026 show that this is no longer true: the installer now sends credentials off the box on every run, and a second staging host serves it.
INJ3CTOR3’s FreePBX implant now uploads the victim’s SIP trunk, AMI, database, and mail-relay credentials to the operator, so disinfecting or rebuilding an infected host no longer ends the exposure. Anyone running FreePBX, Issabel, or Elastix who suspects compromise must rotate the secrets in 17 configuration files, and only after the host is clean.
The infection and persistence code is nearly unchanged; what the operator rotated are the identifiers that were available to defenders since the last time. Each section below pairs a finding with what to do about it.
Key Takeaways
Credentials leave on every run. k.php uploads 17 configuration files to both staging hosts every minute the host stays infected.
The fraud no longer needs your PBX. A stolen trunk secret lets the operator register and place calls as you from anywhere.
Last report’s identifiers have expired. Each build now carries its own watermark, and the webshell gate hash was rotated.
Two staging hosts. Plain-text commands now point to 160[.]119[.]69[.]4, while base64-encoded ones still use 45[.]95[.]147[.]178.
Clean-looking logs and consoles prove nothing. Requests through an encoded space reach the shell without being named in the access log, and trunks are written directly to /etc/asterisk; they do not appear in the FreePBX console.
The Campaign So Far
INJ3CTOR3 has been abusing Asterisk-based phone systems for toll fraud since at least 2020. Check Point Research named the operation that November, when it exploited CVE-2019-19006 in FreePBX and used a basic webshell to read amportal.conf and sip_additional.conf by hand. Unit 42 reported a related operation against Elastix in 2022, Fortinet documented the EncystPHP webshell in January 2026, and our May report covered JOMANGY.
The playbook has held for six years: scan for exposed PBXs, exploit or brute-force a way in, plant a password-gated webshell, and dial out at the victim’s expense. Figure 1 below shows the chain as it stands in the September build, now including the credential upload back to the staging hosts.
Figure 1: INJ3CTOR3 attack chain, September generation. (Source: 0x1da5 GitHub)
What Changed Since Our Last Report
We compared the April artifacts behind our May report with the 9 September collection from both staging hosts, after decoding every layer.
Unchanged: the decoded webshell panel, the encoding chain (base64 in the shell script, base64 again in PHP, then ROT13), the persistence channels, the backdoor account password hash, and the borrowed timestamp. Behavioral detections built on our May report still apply.
Credential Exfiltration: The Implant Is No Longer the Product
The September k.php ends with two new base64-encoded lines, each holding 17 curl commands that upload one configuration file apiece to /hima_data/index.php, one line per staging host (See Figure 2 below). The paths are typed out by hand and cover FreePBX, Issabel, and Elastix layouts. The collector path echoes hima, a backdoor account the takeover script creates. The name goes back further: Check Point’s 2020 INJ3CTOR3 report shows a Telegram post by a user called Hima sharing a tool that scans and cracks SIP ranges, saving its output as HimaResults.
Figure 2: k.php line 34, decoded into 17 file uploads
Three of the cron beacons fetch and run k.php every minute (the others every two or three minutes), so the upload repeats every minute during the infection. Rotating credentials on a still-infected host hands the new secrets to the operator within minutes.
The database password (AMPDBPASS), the MySQL root password, and any AMI password stored there
Outbound mail
/etc/postfix/sasl_passwd
The SMTP relay account, with your mail provider
This opens a second route to fraud. Our May report covered calls placed through the webshell, which require the shell to be alive and to land in the victim’s own call records. With a stolen trunk secret, the operator can register to the carrier from any machine and call as the victim, leaving nothing on the host, unless the carrier also restricts the trunk to the victim’s IP addresses. A successful disinfection stops the first route; only rotation stops the second.
Detection
Network: outbound HTTP POSTs from a PBX to any /hima_data/ path or to either staging host. A PBX seldom needs outbound web access beyond vendor updates, so egress allow-listing closes this channel.
Carrier: alert on trunk registrations from outside your own IP ranges, and on premium or international destinations, off-hours calling, and unusual concurrency. Set spend caps and destination blocks where your carrier offers them.
For Law Enforcement Agencies and CERTs
By design, victims’ credentials were collected on the two staging hosts, which stopped responding in late September 2026. Going offline does not end exposure: hosting providers may still retain server data, and infected PBXs keep trying to upload their credentials every minute to addresses that could be reassigned to someone else.
Both are reasons for law enforcement and national CERTs, which have the legal standing that researchers lack, to work with the providers on preserving that data and sinkholing the addresses, which would also identify victims for notification. We saw the uploads in code; we did not capture one in transit and hold no victim list.
Two Staging Hosts, Split by Encoding
An infected host now talks to both staging hosts, and which one depends on whether the command was written in plain text or base64. The /x takeover script is byte-identical on both.
Reference
Encoding
Points to
k.php line 2 (re-runs /x), eight cron schedules in /x, wr.php’s callback
Plain text
160[.]119[.]69[.]4
Camouflaged cron payloads, login-triggered stager
Base64
45[.]95[.]147[.]178
Credential upload
Base64
Both
In April, all of these pointed to 45[.]95[.]147[.]178. We assess that the operator replaced the address in plain text and never re-encoded the base64 strings; the credential upload, which names both hosts, appears deliberate. This host is distinct from the scanner 160[.]119[.]76[.]250, which is named in our May report.
Defend: block both hosts in both directions, and decode every base64-encoded string in a crontab or shell profile before deciding which hosts a host talks to. A plain-text review would miss every channel that still reaches 45[.]95[.]147[.]178.
The Webshell: Same Program, New Identifiers
Decoded, the September JOMANGY panel is identical to April’s except for the values defenders were told to look for.
Per-build watermark. Our May report advised hunting for trace_e1ebf9066a951be519a24140711839ea, present in every April copy. The September builds carry trace_bd42a8a0d23ae16c85dede7d2abaec05 (45[.]95[.]147[.]178) and trace_7544725ebaaadac217dfaa7ca8e8fe7e (160[.]119[.]69[.]4), so that hunt now misses current infections.
One gate for two generations. JOMANGY and ZenharR share a single hardcoded MD5 gate hash, rotated together from a2f6863413c4192a4abfa360577b9961 to 8b3a1d970fda0c17a0b785a990fb7b6a. Our May report listed the April value under ZenharR only.
A forged administrator session. Behind the gate, the FreePBX button builds an admin session using FreePBX’s own ampuser class and setAdmin(); in our lab, it opened the full console without any password. Therefore, changing the FreePBX admin password affects neither the gate nor this session. (See Figure 3 below)
Figure 3: The panel’s Freepbx and Elastix buttons forge an admin session without a password
Because each of these identifiers changes between builds, the detection approach later in this report focuses on who put a file on disk rather than on what the file contains.
The .htaccess Door and the Access-Log Gap
k.php writes a seven-line .htaccess to /var/www/html/admin/views/. It does not hide the webshell; it unblocks it, and it lets requests reach a copy without naming it.
Simulating an operator and a victim in an isolated environment, we confirmed that a request to a URL containing an encoded space returned a working webshell for the attacker. The access log records only the requested path, never the file that answered, so searching logs for the webshell byits filename can return nothing on a host that is serving it.
Defend: check every .htaccess across the web root for who put it there; one that no package, FreePBX module, or member of your team accounts for is suspect, whatever it contains. Because the takeover script wipes logs, treat log hunting as secondary: requests with %20, %09, or %0A directly after a slash that return 200 are worth a look where logs survive.
What the FreePBX Console Won’t Show You
FreePBX lists the trunks it created from its own database; Asterisk reads whatever is in its configuration files. In our lab, a trunk we wrote directly into /etc/asterisk/pjsip_custom.conf carried a call while the FreePBX Trunks page reported no records (See Figure 4 below). We did not see the campaign plant one, but its root-equivalent accounts and stolen trunk secrets give the operator everything needed to do so.
Figure 4: Our lab trunk, known to Asterisk and carrying calls, invisible in the FreePBX console
Defend: audit from the Asterisk CLI (pjsip show endpoints, pjsip show registrations, sip show peers, sip show registry) and compare with what the console lists. Review the *_custom.conf files for trunks or contexts that nobody on your team added.
What Keeps It There
Before detecting or cleaning, it helps to see the whole apparatus. Everything in Figure 5 is read from /x and k.php: ways the implant stays on the box, and doors allowing the operator to come back, through a system account or a single web request. Each piece can rebuild/repair all others under a minute, which is why removing any one of them on its own fails. (See Figure 5 below)
Figure 5: Persistence channels that rebuild each other, and the backdoors they stay open
Detecting It Without IOCs
The operator rotates hashes, watermarks, gate values, and hosts between builds, so asking whether a file is known-bad quickly stops working. The better question is who put the file there: compare what is on disk with what the package manager or a clean install says it should be.
On the host: triage with beagle.sh
PBX admins can run beagle.sh, a report-only script that makes no changes to the host, to check a PBX server for signs of compromise. (See Figure 6 below)
Check
What it flags
Packed shells
Several identical, same-size PHP files across unrelated directories
Locked files
chattr +i or +a under the web root or in hidden directories
Unowned .htaccess
An .htaccess no installed package accounts for
Self-rebuilding cron
A cron line that downloads a file and hands it to a shell
Accounts
An extra UID-0 account, or a full-permission FreePBX admin, nobody created
Blocklist
Addresses dropped in and out by iptables outside fail2ban’s chains
Figure 6: beagle.sh (Source: 0x1da5 GitHub)
The script separated one infected server from one clean server of the same FreePBX version, a sample of one, so expect some legitimate findings. However, it cannot tell you whether the credentials have already been left: that happens during the first cron run, within a minute of infection, and long before anyone scans. The upload leaves no file behind, and the takeover script wipes what might have recorded it: the web server, Asterisk, cron and audit logs, plus shell and MySQL histories, which makes forensic timelines hard to reconstruct.
With telemetry
The most distinctive actions leave little on disk; in our detonation, backdoor accounts were created and deleted 27 seconds apart. These eleven behaviors are detection strategies to build into your own tooling:
Layer
Behavior
What it catches
Host
crond spawns a shell that downloads a file and runs it
The takeover script on its single run, before persistence and before credentials leave
Host
The web server account spawns a shell
The webshell’s command box in use
Host
A cron child rewrites the crontab every minute without reading it first
Beacon reinstallation
Host
chattr +i or touch -r on a file in the web root
The lock and the borrowed timestamp
Host
Twelve PHP files were written to the web root in the same second
The webshell copies, as they are written; fan-out
Network
The PBX contacts staging host roughly every 60 seconds
The beacon’s rhythm, whatever the address
Network
Many configuration files read, then outbound POST requests
Credentials leaving
Web
A request with leading encoded whitespace returns 200 for a path not on disk
The .htaccess door
Decoy
Any read of a decoy config file that the implant reads, but nothing legitimate does
Credential collection, with no false positives by design
Phone
Channels originate over AMI or the CLI outside your dial plan
A call asking for nothing legitimate
Phone
CDRs with premium destinations, off-hours calling and unusual concurrency
The fraud itself
The last two catch the fraud rather than the machinery, whatever the files are called, and whether you ever find the shell. The host rows need process telemetry that PBX appliances rarely have, which is part of why so many stay infected.
Why Cleanup Fails, and the Order That Works
First move
Why it fails on its own
Delete the webshell
Cron re-runs k.php within minutes and rewrites all 12 copies, the .htaccess, and the immutable flags.
Patch FreePBX
Sangoma’s advisory for CVE-2025-57819 states the fix prevents new exploitation but does not clean a compromised system.
Change the admin password
The gate and the forged session never use it, and the backdoor accounts bypass the FreePBX login.
Shadowserver data showed more than 900 compromised FreePBX instances in February 2026; over 700 of them were still compromised in May. Rebuilding from a clean image is the most reliable fix; if you clean in place, work from the system layer up, because it replants everything above it.
Preserve first
The takeover script truncates logs, then deletes them, and clears shell and database history, so evidence shrinks with every run:
Cut the host off from the internet, or at least block all outbound traffic except to your SIP carrier. Blocking only the two known staging hosts is not enough if the operator has moved. With no route out, the minute-by-minute downloads fail, and nothing more is uploaded. One local loop survives: a watchdog cron line re-runs the cached copy of k.php at /var/lib/asterisk/bin/zen2 every minute, rebuilding the webshells offline, which is why cron comes first in the cleanup below.
Capture all crontabs and the eight backups listed below, /etc/passwd, /etc/shadow, shell profiles, and the web root with lsattr output and change times.
Export the FreePBX ampusers table, the call records database, and the Asterisk full log, and ask your carrier to preserve CDRs and registration logs.
Then clean, in this order
Cron and its spares. Clear root’s crontab in one go, so the restore and watchdog lines are removed. Then kill any running zen2, devnull2, or serv processes; killed earlier, the watchdog restarts them within a minute. Remove the k.php beacons (/var/lib/asterisk/bin/zen2, devnull2, zen222, devnull312, devnull212, /tmp/.cache/update, /dev/shm/.systemd/kernel). Unlock (chattr -i, -a) and delete the eight crontab backups: /usr/lib/.systemd/.cache, /usr/share/.fonts/.config, /var/lib/.dbus/.data, /var/tmp/.X11/.Xauthority, /opt/.local/.bashrc, /var/cache/.fontconfig/.cfg, /etc/.ssl/.cert, and /root/.config/.pref.
Login and boot triggers. Remove the base64 stager from /root/.bash_profile, /root/.bashrc, and /etc/rc.local.
Accounts and SSH. Remove every extra UID-0 account and any account whose /etc/shadow hash begins with $1$nRz1Cbtk$ (legitimate service accounts with that hash need new passwords, not deletion). Restore sshd_config, where root login was re-enabled.
Web application. Remove the 12 webshell copies, the .htaccess, the freepbxusers row in ampusers, and /var/www/html/admin/modules/freepbx_ha/license.php.
Credentials. Only now rotate the secrets in the 17 files and across every account on the host.
Conclusion
The hard part of the campaign used to be getting the implant off the box, and that has not changed. What has changed is that the box is no longer the whole problem: an organization that rebuilds but does not rotate has removed the operator’s calling platform and handed over its carrier account.
The code ties this generation to the actor in our May report through the takeover script, backdoor hash, and staging host, and a gate rotated in step across JOMANGY and ZenharR.
The operator is now rotating exactly the strings defenders were given, so detections built on provenance and behavior will outlast this build, and detections built on its hashes will not. CRIL continues to monitor INJ3CTOR3’s infrastructure.
Indicators of Compromise
Hashes and strings rotate between builds; use them to confirm a finding, not as your only detection.
In May, Cyble Research & Intelligence Labs (CRIL) documented JOMANGY, a PHP webshell generation deployed by INJ3CTOR3 with self-healing persistence channels and a built-in toll-fraud dialer.
Back then, the fraud ran through the victim’s own PBX, so removing the implant would have stopped it. Artifacts we collected from the operator’s C2 staging servers during mid-September 2026 show that this is no longer true: the installer now sends credentials off the box on every run, and a second staging host serves it.
INJ3CTOR3’s FreePBX implant now uploads the victim’s SIP trunk, AMI, database, and mail-relay credentials to the operator, so disinfecting or rebuilding an infected host no longer ends the exposure. Anyone running FreePBX, Issabel, or Elastix who suspects compromise must rotate the secrets in 17 configuration files, and only after the host is clean.
The infection and persistence code is nearly unchanged; what the operator rotated are the identifiers that were available to defenders since the last time. Each section below pairs a finding with what to do about it.
Key Takeaways
Credentials leave on every run. k.php uploads 17 configuration files to both staging hosts every minute the host stays infected.
The fraud no longer needs your PBX. A stolen trunk secret lets the operator register and place calls as you from anywhere.
Last report’s identifiers have expired. Each build now carries its own watermark, and the webshell gate hash was rotated.
Two staging hosts. Plain-text commands now point to 160[.]119[.]69[.]4, while base64-encoded ones still use 45[.]95[.]147[.]178.
Clean-looking logs and consoles prove nothing. Requests through an encoded space reach the shell without being named in the access log, and trunks are written directly to /etc/asterisk; they do not appear in the FreePBX console.
The Campaign So Far
INJ3CTOR3 has been abusing Asterisk-based phone systems for toll fraud since at least 2020. Check Point Research named the operation that November, when it exploited CVE-2019-19006 in FreePBX and used a basic webshell to read amportal.conf and sip_additional.conf by hand. Unit 42 reported a related operation against Elastix in 2022, Fortinet documented the EncystPHP webshell in January 2026, and our May report covered JOMANGY.
The playbook has held for six years: scan for exposed PBXs, exploit or brute-force a way in, plant a password-gated webshell, and dial out at the victim’s expense. Figure 1 below shows the chain as it stands in the September build, now including the credential upload back to the staging hosts.
Figure 1: INJ3CTOR3 attack chain, September generation. (Source: 0x1da5 GitHub)
What Changed Since Our Last Report
We compared the April artifacts behind our May report with the 9 September collection from both staging hosts, after decoding every layer.
Unchanged: the decoded webshell panel, the encoding chain (base64 in the shell script, base64 again in PHP, then ROT13), the persistence channels, the backdoor account password hash, and the borrowed timestamp. Behavioral detections built on our May report still apply.
Credential Exfiltration: The Implant Is No Longer the Product
The September k.php ends with two new base64-encoded lines, each holding 17 curl commands that upload one configuration file apiece to /hima_data/index.php, one line per staging host (See Figure 2 below). The paths are typed out by hand and cover FreePBX, Issabel, and Elastix layouts. The collector path echoes hima, a backdoor account the takeover script creates. The name goes back further: Check Point’s 2020 INJ3CTOR3 report shows a Telegram post by a user called Hima sharing a tool that scans and cracks SIP ranges, saving its output as HimaResults.
Figure 2: k.php line 34, decoded into 17 file uploads
Three of the cron beacons fetch and run k.php every minute (the others every two or three minutes), so the upload repeats every minute during the infection. Rotating credentials on a still-infected host hands the new secrets to the operator within minutes.
The database password (AMPDBPASS), the MySQL root password, and any AMI password stored there
Outbound mail
/etc/postfix/sasl_passwd
The SMTP relay account, with your mail provider
This opens a second route to fraud. Our May report covered calls placed through the webshell, which require the shell to be alive and to land in the victim’s own call records. With a stolen trunk secret, the operator can register to the carrier from any machine and call as the victim, leaving nothing on the host, unless the carrier also restricts the trunk to the victim’s IP addresses. A successful disinfection stops the first route; only rotation stops the second.
Detection
Network: outbound HTTP POSTs from a PBX to any /hima_data/ path or to either staging host. A PBX seldom needs outbound web access beyond vendor updates, so egress allow-listing closes this channel.
Carrier: alert on trunk registrations from outside your own IP ranges, and on premium or international destinations, off-hours calling, and unusual concurrency. Set spend caps and destination blocks where your carrier offers them.
For Law Enforcement Agencies and CERTs
By design, victims’ credentials were collected on the two staging hosts, which stopped responding in late September 2026. Going offline does not end exposure: hosting providers may still retain server data, and infected PBXs keep trying to upload their credentials every minute to addresses that could be reassigned to someone else.
Both are reasons for law enforcement and national CERTs, which have the legal standing that researchers lack, to work with the providers on preserving that data and sinkholing the addresses, which would also identify victims for notification. We saw the uploads in code; we did not capture one in transit and hold no victim list.
Two Staging Hosts, Split by Encoding
An infected host now talks to both staging hosts, and which one depends on whether the command was written in plain text or base64. The /x takeover script is byte-identical on both.
Reference
Encoding
Points to
k.php line 2 (re-runs /x), eight cron schedules in /x, wr.php’s callback
Plain text
160[.]119[.]69[.]4
Camouflaged cron payloads, login-triggered stager
Base64
45[.]95[.]147[.]178
Credential upload
Base64
Both
In April, all of these pointed to 45[.]95[.]147[.]178. We assess that the operator replaced the address in plain text and never re-encoded the base64 strings; the credential upload, which names both hosts, appears deliberate. This host is distinct from the scanner 160[.]119[.]76[.]250, which is named in our May report.
Defend: block both hosts in both directions, and decode every base64-encoded string in a crontab or shell profile before deciding which hosts a host talks to. A plain-text review would miss every channel that still reaches 45[.]95[.]147[.]178.
The Webshell: Same Program, New Identifiers
Decoded, the September JOMANGY panel is identical to April’s except for the values defenders were told to look for.
Per-build watermark. Our May report advised hunting for trace_e1ebf9066a951be519a24140711839ea, present in every April copy. The September builds carry trace_bd42a8a0d23ae16c85dede7d2abaec05 (45[.]95[.]147[.]178) and trace_7544725ebaaadac217dfaa7ca8e8fe7e (160[.]119[.]69[.]4), so that hunt now misses current infections.
One gate for two generations. JOMANGY and ZenharR share a single hardcoded MD5 gate hash, rotated together from a2f6863413c4192a4abfa360577b9961 to 8b3a1d970fda0c17a0b785a990fb7b6a. Our May report listed the April value under ZenharR only.
A forged administrator session. Behind the gate, the FreePBX button builds an admin session using FreePBX’s own ampuser class and setAdmin(); in our lab, it opened the full console without any password. Therefore, changing the FreePBX admin password affects neither the gate nor this session. (See Figure 3 below)
Figure 3: The panel’s Freepbx and Elastix buttons forge an admin session without a password
Because each of these identifiers changes between builds, the detection approach later in this report focuses on who put a file on disk rather than on what the file contains.
The .htaccess Door and the Access-Log Gap
k.php writes a seven-line .htaccess to /var/www/html/admin/views/. It does not hide the webshell; it unblocks it, and it lets requests reach a copy without naming it.
Simulating an operator and a victim in an isolated environment, we confirmed that a request to a URL containing an encoded space returned a working webshell for the attacker. The access log records only the requested path, never the file that answered, so searching logs for the webshell byits filename can return nothing on a host that is serving it.
Defend: check every .htaccess across the web root for who put it there; one that no package, FreePBX module, or member of your team accounts for is suspect, whatever it contains. Because the takeover script wipes logs, treat log hunting as secondary: requests with %20, %09, or %0A directly after a slash that return 200 are worth a look where logs survive.
What the FreePBX Console Won’t Show You
FreePBX lists the trunks it created from its own database; Asterisk reads whatever is in its configuration files. In our lab, a trunk we wrote directly into /etc/asterisk/pjsip_custom.conf carried a call while the FreePBX Trunks page reported no records (See Figure 4 below). We did not see the campaign plant one, but its root-equivalent accounts and stolen trunk secrets give the operator everything needed to do so.
Figure 4: Our lab trunk, known to Asterisk and carrying calls, invisible in the FreePBX console
Defend: audit from the Asterisk CLI (pjsip show endpoints, pjsip show registrations, sip show peers, sip show registry) and compare with what the console lists. Review the *_custom.conf files for trunks or contexts that nobody on your team added.
What Keeps It There
Before detecting or cleaning, it helps to see the whole apparatus. Everything in Figure 5 is read from /x and k.php: ways the implant stays on the box, and doors allowing the operator to come back, through a system account or a single web request. Each piece can rebuild/repair all others under a minute, which is why removing any one of them on its own fails. (See Figure 5 below)
Figure 5: Persistence channels that rebuild each other, and the backdoors they stay open
Detecting It Without IOCs
The operator rotates hashes, watermarks, gate values, and hosts between builds, so asking whether a file is known-bad quickly stops working. The better question is who put the file there: compare what is on disk with what the package manager or a clean install says it should be.
On the host: triage with beagle.sh
PBX admins can run beagle.sh, a report-only script that makes no changes to the host, to check a PBX server for signs of compromise. (See Figure 6 below)
Check
What it flags
Packed shells
Several identical, same-size PHP files across unrelated directories
Locked files
chattr +i or +a under the web root or in hidden directories
Unowned .htaccess
An .htaccess no installed package accounts for
Self-rebuilding cron
A cron line that downloads a file and hands it to a shell
Accounts
An extra UID-0 account, or a full-permission FreePBX admin, nobody created
Blocklist
Addresses dropped in and out by iptables outside fail2ban’s chains
Figure 6: beagle.sh (Source: 0x1da5 GitHub)
The script separated one infected server from one clean server of the same FreePBX version, a sample of one, so expect some legitimate findings. However, it cannot tell you whether the credentials have already been left: that happens during the first cron run, within a minute of infection, and long before anyone scans. The upload leaves no file behind, and the takeover script wipes what might have recorded it: the web server, Asterisk, cron and audit logs, plus shell and MySQL histories, which makes forensic timelines hard to reconstruct.
With telemetry
The most distinctive actions leave little on disk; in our detonation, backdoor accounts were created and deleted 27 seconds apart. These eleven behaviors are detection strategies to build into your own tooling:
Layer
Behavior
What it catches
Host
crond spawns a shell that downloads a file and runs it
The takeover script on its single run, before persistence and before credentials leave
Host
The web server account spawns a shell
The webshell’s command box in use
Host
A cron child rewrites the crontab every minute without reading it first
Beacon reinstallation
Host
chattr +i or touch -r on a file in the web root
The lock and the borrowed timestamp
Host
Twelve PHP files were written to the web root in the same second
The webshell copies, as they are written; fan-out
Network
The PBX contacts staging host roughly every 60 seconds
The beacon’s rhythm, whatever the address
Network
Many configuration files read, then outbound POST requests
Credentials leaving
Web
A request with leading encoded whitespace returns 200 for a path not on disk
The .htaccess door
Decoy
Any read of a decoy config file that the implant reads, but nothing legitimate does
Credential collection, with no false positives by design
Phone
Channels originate over AMI or the CLI outside your dial plan
A call asking for nothing legitimate
Phone
CDRs with premium destinations, off-hours calling and unusual concurrency
The fraud itself
The last two catch the fraud rather than the machinery, whatever the files are called, and whether you ever find the shell. The host rows need process telemetry that PBX appliances rarely have, which is part of why so many stay infected.
Why Cleanup Fails, and the Order That Works
First move
Why it fails on its own
Delete the webshell
Cron re-runs k.php within minutes and rewrites all 12 copies, the .htaccess, and the immutable flags.
Patch FreePBX
Sangoma’s advisory for CVE-2025-57819 states the fix prevents new exploitation but does not clean a compromised system.
Change the admin password
The gate and the forged session never use it, and the backdoor accounts bypass the FreePBX login.
Shadowserver data showed more than 900 compromised FreePBX instances in February 2026; over 700 of them were still compromised in May. Rebuilding from a clean image is the most reliable fix; if you clean in place, work from the system layer up, because it replants everything above it.
Preserve first
The takeover script truncates logs, then deletes them, and clears shell and database history, so evidence shrinks with every run:
Cut the host off from the internet, or at least block all outbound traffic except to your SIP carrier. Blocking only the two known staging hosts is not enough if the operator has moved. With no route out, the minute-by-minute downloads fail, and nothing more is uploaded. One local loop survives: a watchdog cron line re-runs the cached copy of k.php at /var/lib/asterisk/bin/zen2 every minute, rebuilding the webshells offline, which is why cron comes first in the cleanup below.
Capture all crontabs and the eight backups listed below, /etc/passwd, /etc/shadow, shell profiles, and the web root with lsattr output and change times.
Export the FreePBX ampusers table, the call records database, and the Asterisk full log, and ask your carrier to preserve CDRs and registration logs.
Then clean, in this order
Cron and its spares. Clear root’s crontab in one go, so the restore and watchdog lines are removed. Then kill any running zen2, devnull2, or serv processes; killed earlier, the watchdog restarts them within a minute. Remove the k.php beacons (/var/lib/asterisk/bin/zen2, devnull2, zen222, devnull312, devnull212, /tmp/.cache/update, /dev/shm/.systemd/kernel). Unlock (chattr -i, -a) and delete the eight crontab backups: /usr/lib/.systemd/.cache, /usr/share/.fonts/.config, /var/lib/.dbus/.data, /var/tmp/.X11/.Xauthority, /opt/.local/.bashrc, /var/cache/.fontconfig/.cfg, /etc/.ssl/.cert, and /root/.config/.pref.
Login and boot triggers. Remove the base64 stager from /root/.bash_profile, /root/.bashrc, and /etc/rc.local.
Accounts and SSH. Remove every extra UID-0 account and any account whose /etc/shadow hash begins with $1$nRz1Cbtk$ (legitimate service accounts with that hash need new passwords, not deletion). Restore sshd_config, where root login was re-enabled.
Web application. Remove the 12 webshell copies, the .htaccess, the freepbxusers row in ampusers, and /var/www/html/admin/modules/freepbx_ha/license.php.
Credentials. Only now rotate the secrets in the 17 files and across every account on the host.
Conclusion
The hard part of the campaign used to be getting the implant off the box, and that has not changed. What has changed is that the box is no longer the whole problem: an organization that rebuilds but does not rotate has removed the operator’s calling platform and handed over its carrier account.
The code ties this generation to the actor in our May report through the takeover script, backdoor hash, and staging host, and a gate rotated in step across JOMANGY and ZenharR.
The operator is now rotating exactly the strings defenders were given, so detections built on provenance and behavior will outlast this build, and detections built on its hashes will not. CRIL continues to monitor INJ3CTOR3’s infrastructure.
Indicators of Compromise
Hashes and strings rotate between builds; use them to confirm a finding, not as your only detection.
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ultralytics. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-118613.
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ultralytics. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-118614.
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ultralytics. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-118615.