CVE-2026-109311 vLLM before 0.29.0 Heap Overflow DoS via IAMF Audio Transcription Upload
Authenticated attackers can crash the vLLM API process by uploading malformed IAMF audio files, causing a heap overflow in the underlying FFmpeg parser.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-109311?
CVE-2026-109311 is a high-severity memory corruption vulnerability in vllm-project vllm, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
vLLM before 0.29.0 passes uploaded audio to the PyAV/FFmpeg av.open() fallback with only a file-size check, exposing FFmpeg's IAMF parser heap overflow. Authenticated remote attackers can repeatedly upload malformed IAMF containers to /v1/audio/transcriptions, corrupting the heap and crashing the API process.
Weakness: CWE-20
Which versions are affected by CVE-2026-109311?
How do I fix CVE-2026-109311?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-109311 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109311 exists.
Sources
Also known as GHSA-8wc5-pcgr-pg48, GHSA-m52c-39rh-f3gp, MINI-6g9p-w7v5-v4mq, MINI-q3f2-252w-xjpm, MINI-whh4-v64g-jv53.