Changed since version 6

• Renumbered sources to today's list: S1 The Hacker News, S2 FortiGuard, S3 SecurityWeek, S4 CISA KEV catalog, S5 CISA alert; Unit 42 kept as S6 from draft v6.
• Added the iked VPN validation bypass for tagged sessions to what_happened, verdict, verify, enumerate, recover and debrief [S1].
• Added note that pM.js self-deletes, so its absence proves nothing [S1].
• Added eradicate steps, which were empty in v6 [S1][S2][S6].
• Added timeline, re-enter triggers and coverage checks.
• Noted that the 2026-10-20 story corroborates nothing new [S3].

What happened

• CL-STA-0954 (UNC5820) got initial access through FortiManager FortiJump (CVE-2024-47575) at a telecom MSP [S1][S6].
• The actor exfiltrated configs, cryptographic material and database files for 500+ managed FortiGates, then opened unauthorized SSL-VPN sessions to perimeter firewalls [S1][S6].
• It exploited CVE-2025-61624, an authenticated FortiOS CLI path traversal, to deploy PEERSTITCH via an auto-script fetching five components from 23.240.77[.]233:8085 [S1][S6].
• PEERSTITCH ptrace-injects into /bin/miglogd and /bin/iked. In iked, a tag in a VPN session's injection buffer makes the session bypass default FortiOS security validations [S1].
• The actor used Apache mod_md for an SSH reverse shell, impersonated FortiManager to pull configs, killed logging and deleted rogue admins and auto-scripts after use [S1][S6].
• CISA added CVE-2025-61624 to KEV on 2026-10-16 based on evidence of active exploitation [S4][S5].

Timeline

Detect

FortiGate auto-script objects with path traversal names · FortiOS system event / config change logs (syslog or FortiAnalyzer forward)

index=* devid=* type="event" subtype="system" (cfgpath="system.auto-script" OR msg="*auto-script*") (cfgobj="*../*" OR msg="*../*") | stats count min(_time) as first_seen max(_time) as last_seen values(action) as action values(cfgobj) as cfgobj values(msg) as msg by devname user ui

A hit means: An auto-script object with ../ in its name was created, edited or deleted. Such objects delivered PEERSTITCH and the reverse shell [S1][S6]. Treat as likely compromise. The actor deletes these objects after use, so a delete event alone matters [S1].

Traffic, web or SSL-VPN sessions involving campaign infrastructure · FortiGate traffic, web filter and VPN event logs; proxy/egress logs

index=* (srcip IN ("23.240.77.233","47.18.167.159","45.32.41.202","198.199.122.22") OR dstip IN ("23.240.77.233","47.18.167.159","45.32.41.202","198.199.122.22") OR remip IN ("23.240.77.233","47.18.167.159","45.32.41.202","198.199.122.22") OR url="*/pM.js" OR url="*/acme/new-acct*" OR url="*/acme/finalize/*" OR url="*/acme/order/*" OR url="*/acme/authz/*") | stats count min(_time) as first_seen max(_time) as last_seen values(dstport) as dstport values(url) as url values(action) as action values(user) as user by devname srcip dstip

A hit means: A device contacted campaign infrastructure. Port 8085 fetches of pM.js match the component download [S1][S6]. Port 8084 /acme/ paths match the mod_md reverse-shell channel [S6]. Inbound SSL-VPN logins from these IPs match stolen-credential use [S6]. ACME paths alone can be benign if the host is not a campaign IP.

Logging daemons killed, crashlogs cleared, or FortiGateCloud admin activity · FortiOS CLI audit and system event logs

index=* devid=* (msg="*killall*miglogd*" OR msg="*killall*syslogd*" OR msg="*crashlog clear*" OR user="FortiGateCloud") | stats count min(_time) as first_seen max(_time) as last_seen values(msg) as msg values(ui) as ui by devname user

A hit means: Someone stopped logging or cleared crashlogs, or an admin named FortiGateCloud acted on the device; all reported as actor tradecraft [S1][S6]. Also check each device's syslog stream for gaps; a successful kill produces silence, not events.

Rogue Virtual FortiGate registration on FortiManager · FortiManager event / device management logs

index=* ("FMG-VMTM23017412" OR ("Virtual FortiGate" AND "localhost") OR ".tm") devid=* | stats count min(_time) as first_seen max(_time) as last_seen values(msg) as msg by devname

A hit means: The serial or name of the rogue Virtual FortiGate appears, or a .tm archive is referenced [S6]. Treat the FortiManager and every device it manages as in scope. Absence does not clear you; the actor may use other serials.

Verify

• Pull config revisions on each FortiGate. Look for auto-script objects containing ../, unexpected sniffer configs, and admins or VPN groups created then deleted [S1][S6].
• Run 'diagnose debug crashlog read' and look for Signal 11 crashes in miglogd, iked or syslogd [S6].
• With vendor support, check miglogd and iked memory for injected executable regions and the patches Unit 42 lists [S1][S6].
• Do not treat clean VPN authentication logs as proof of no access. Hooked iked lets tagged sessions skip FortiOS validation [S1].
• Look for pM.js, a.js, a.wasm, b.js, dd, index.js, index.wasm, ipssem.js and lldprx on the device. pM.js self-deletes, so its absence proves nothing [S1][S6].
• Check the mod_md config and job files for an attacker ACME server or /bin/node as a challenge handler [S6].

Scope

Affected

• FortiOS, FortiPAM, FortiProxy and FortiSwitchManager (CVE-2025-61624) [S2][S5]
• FortiManager (CVE-2024-47575), the initial access in this campaign [S1]
• FortiGates managed by a compromised FortiManager, whose configs and keys were exfiltrated [S1]

Only if

• CVE-2025-61624: the attacker is authenticated with an admin profile that has read-write permissions [S5]
• In this campaign, that access came from credentials taken via the compromised FortiManager [S1][S6]

Not affected if

None stated by the sources.

Fixed in: See Fortinet FG-IR-26-122 [S2]. Fixed versions are not stated in the provided material.

Enumerate

• Every FortiOS, FortiPAM, FortiProxy, FortiSwitchManager and FortiManager instance, with its running version.
• For each FortiManager: all registered devices, any unknown Virtual FortiGates, .tm archives, and which FortiGates it manages.
• All admin accounts, VPN users and groups, including deleted ones visible in config revisions.
• Secrets stored in FortiGate configs: admin and VPN credentials, pre-shared keys, certificates, RADIUS/LDAP binds.
• Management and FGFM (TCP 541) exposure per device, and which hosts each FortiGate accepts management connections from.
• VPN sessions on each FortiGate since first suspected access, compared against expected users and sources.

Contain

• Before patching or rebooting, export config revisions, event logs and crashlogs. With vendor support, capture memory of miglogd and iked. PEERSTITCH lives in process memory; a reboot destroys those artifacts and cannot be undone [S1][S6].
• Block 23.240.77.233, 47.18.167.159, 45.32.41.202 and 198.199.122.22 at egress and for SSL-VPN [S1][S6].
• Block outbound SSH from firewall management addresses unless required [S1].
• Restrict management and FGFM access to known FortiManager and admin hosts, since the actor impersonated FortiManager [S1]. Remove internet exposure of FortiManager and admin interfaces.
• Disable unknown admins and VPN accounts. Remove unauthorized sniffer configs and rogue FortiManager device registrations [S6].
• If a FortiManager may be compromised, rotate every credential and key stored in FortiGate configs [S1]. Data already taken stays exposed after rotation.
• Apply FG-IR-26-122 [S2] and the FortiManager fix for CVE-2024-47575. Where patching lags, confirm FortiGuard virtual patch FG-VD-59270.0day (FMWP db 25.120) is in place [S2].

Eradicate

• Remove rogue auto-script objects, admin accounts and VPN groups [S1].
• Clear injected code from miglogd and iked; with vendor guidance, reimage or reinstall firmware from a trusted image [S1][S6].
• Remove mod_md reverse-shell configuration and dropped components (ipssem.js, lldprx, index.js, index.wasm) [S1][S6].
• Close the root causes: patch CVE-2024-47575 on FortiManager and CVE-2025-61624 on affected products [S1][S2].

Recover

• Before restoring, confirm patched firmware, a config matching a known-good baseline, and rotated secrets [S2].
• Confirm syslog flows continuously from each device and crashlogs are retained.
• Afterwards, keep the four hunts running. Alert on new auto-scripts, short-lived admins, sniffer config changes, outbound SSH from firewalls, unexpected FGFM peers, unexpected VPN sessions and logging gaps [S1][S6].

Re-enter the loop when

• Fortinet updates FG-IR-26-122 with fixed versions, new affected products or a change in exploitation status.
• New IoCs, hashes or Virtual FortiGate serials are published for CL-STA-0954.
• Any FortiManager is found compromised: every FortiGate it manages joins scope.
• A source confirms or refutes a role for CVE-2024-26008 or CVE-2024-26009.
• Evidence that PEERSTITCH survives reboot or firmware reinstall.

Debrief

• Record each device, version, patch date, evidence captured, and hunt results.
• Record which secrets were rotated and when, and any logging gaps found.
• Record VPN sessions that could not be validated, given the iked bypass [S1].
• Gap: no fixed versions in the provided material.
• Gap: roles of CVE-2024-26008 and CVE-2024-26009 are not explained; one story calls CVE-2024-26008 an alias of FortiJump, which the sources do not support [S3].
• Gap: whether PEERSTITCH survives a reboot is not stated.

Detection coverage — checked automatically

Checked automatically 2026-11-01 01:59Z from public sources: 18 published, 27 nothing found, 0 not machine-checkable, 0 failed. "Nothing found" means the public source answered and had nothing, as of that moment; a feed covers only its newest posts. Re-checked daily.

Exposure queries — generated automatically

vuln:CVE-2024-47575

vuln:CVE-2024-26008

vuln:CVE-2025-61624

cpe:"cpe:/a:fortinet:fortiproxy"

product:"Fortiproxy"

host.services: (software.product = "Fortiproxy")

cpe:"cpe:/a:fortinet:fortiswitchmanager"

product:"Fortiswitchmanager"

host.services: (software.product = "Fortiswitchmanager")

cpe:"cpe:/a:fortinet:fortimanager"

product:"Fortimanager"

host.services: (software.product = "Fortimanager")

cpe:"cpe:/a:fortinet:fortimanager_cloud"

product:"Fortimanager Cloud"

host.services: (software.product = "Fortimanager Cloud")

http.title:"FortiManager"

http.title:"FortiProxy"

Internet-wide count, trend

Shodan's count of matching services on the whole internet, one point a day; the scope (your ranges) is never part of it. A count moves with Shodan's crawl as much as with patching, so read the direction, not the digit.

NVD names 2 more affected products (libraries and embedders); the CVE query covers them where Shodan has fingerprinted the version.

Banner spellings: a model read 6 from the NVD names and this card's text (former and marketing names, console titles); 2 matched something on Shodan and are shown above, the rest were dropped.

Scope every query in your own tool, never in a shared document: Shodan `net:<your_ranges>`, `org:"<your_org>"` or `hostname:<your_domain>` (or a Shodan Monitor network alert, which applies the scope for you); Censys `host.ip: <your_ranges>` or `host.dns.names: <your_domain>`. Then compare the banner version with the affected range. Generated automatically 2026-11-01 01:59Z from the CVE ids and NVD's CPE configurations, each Shodan query counted against Shodan itself; re-built daily with the coverage check.

Open questions

• What are the fixed versions for CVE-2025-61624 per product?
• Does CVE-2024-26008 or CVE-2024-26009 play any role? The 2026-10-20 story's alias claim is unsupported, and its own linked source returned unrelated content [S3].
• What do the '8550 / 169.254.0.1' markers in pipeline behavior notes mean for detecting tagged VPN sessions? Not explained in the provided text.
• Does PEERSTITCH persist across reboot?
• The Unit 42 report is carried from draft v6 as S6; it is not in today's source list and its details should be rechecked against the original.
• Brief date (2026-10-16) predates two thread stories (10-19, 10-20); confirm intended ordering.

Sources

• [S1] https://thehackernews.com/2026/10/attackers-exploit-fortios-flaw-to.html · The Hacker News
• [S2] https://fortiguard.fortinet.com/psirt/FG-IR-26-122 · FortiGuard Labs
• [S3] https://www.securityweek.com/exploited-fortinet-bug-linked-to-stealthy-fortigate-implant-in-telecom-hack/ · SecurityWeek
• [S4] https://www.cisa.gov/known-exploited-vulnerabilities-catalog · CISA
• [S5] https://www.cisa.gov/news-events/alerts/2026/10/16/cisa-adds-two-known-exploited-vulnerabilities-catalog · CISA

Public OSINT only. AI-generated by the pipeline; structure follows the DAIR model from Dynamic Incident Response (Joshua Wright). Published automatically once it crosses the publish bar.