FortiManager: format string vulnerability

FortiManager and FortiAnalyzer

FortiManager vulnerable to format string vulnerability, allowing authenticated attackers to execute unauthorized code.

Do this now

Check the vendor advisory for a fix to FortiManager and restrict administrator access meanwhile.

Who should check: teams running VPN & firewalls

First seen: 10 Nov 2026
Last update: 10 Nov 2026, 21:17 UTC
Source: news
On the menu as: VPN & firewalls

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## FortiManager: format string vulnerability
Severity: unknown. Patch status: fix status unknown.
Affected: FortiManager and FortiAnalyzer

FortiManager vulnerable to format string vulnerability, allowing authenticated attackers to execute unauthorized code.

## Steps
1. This touches infrastructure (vpn-edge). Look in terraform, ansible, cloud-init, Dockerfiles and docs for the product and version we run. If it isn't in the repo, say so and list what a human should check on the box.
2. No source names a fix yet; check the vendor advisory. Until one ships: restrict network access to it.

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://fortiguard.fortinet.com/psirt/FG-IR-26-220 https://fortiguard.fortinet.com/psirt/FG-IR-26-190
https://pwned.coffee/i/fortimanager-format-string-vulnerability

Timeline

10 Nov 2026, 21:17 UTC
Reported by fortiguard.fortinet.com: Arbitrary file write and delete in JSON API
10 Nov 2026
First reported.

Receipt

Exploitation: No known exploitation
Checked by hand “Fortinet FG-IR-26-220: "A Use of Externally-Controlled Format String [CWE-134] in FortiManager, FortiAnalyzer, FortiManager Cloud and FortiAnalyzer Cloud API"; the stored name listed four product variants.” source
Score: No CVSS published yet: severity unknown.
Last checked: 13 Nov 2026, 16:26 UTC

Sources: KEV – CVE record – Vendor ✓

Sources

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