CVE-2026-40281
CRITICALGotenberg is a Docker-powered stateless API for PDF files. In versions 8.30.1 and earlier, the metadata write endpoint validates metadata keys for control characters but leaves metadata…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Description
Gotenberg is a Docker-powered stateless API for PDF files. In versions 8.30.1 and earlier, the metadata write endpoint validates metadata keys for control characters but leaves metadata values unsanitized. A newline character in a metadata value splits the ExifTool stdin line into two separate arguments, allowing injection of arbitrary ExifTool pseudo-tags such as -FileName, -Directory, -SymLink, and -HardLink. This is a bypass of the incomplete key-sanitization fix introduced in v8.30.1. An unauthenticated attacker can rename or move any PDF being processed to an arbitrary path in the container filesystem, overwrite arbitrary files, or create symlinks and hard links at arbitrary paths.
Affected Products
gotenbergthecodingmachineDetection & mitigation playbook
Vendor / applianceDetect
Inventory every thecodingmachine gotenberg deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the thecodingmachine gotenberg security patch or hotfix for CVE-2026-40281 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-40281 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-40281. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40281 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-40281 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.