---
id: CVE-2026-109311
title: >-
  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
summary: >-
  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 /v…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-20
published: '2026-10-12'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T17:17:25.730'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109311'
references:
  - url: >-
      https://github.com/vllm-project/vllm/security/advisories/GHSA-m52c-39rh-f3gp
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/vllm-before-0.29.0-heap-overflow-dos-via-iamf-audio-transcription-upload
    label: disclosure@vulncheck.com
tags:
  - nvd
ingestedAt: '2026-10-12T18:00:08.198Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.