---
id: CVE-2026-30754
title: A memory corruption vulnerability exists in FFmpeg before 8.1
summary: >-
  A memory corruption vulnerability exists in FFmpeg before 8.1. The RTP
  encoding process. In the nal_send function in libavformat/rtpenc_h264_hevc.c,
  a negative size parameter (size=-3) is passed to memcpy when transmitting
  H.264/HEVC str…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-787
published: '2026-09-08'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T16:17:02.720'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-30754'
references:
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20746'
    label: cve@mitre.org
  - url: 'https://gist.github.com/momo-trip/4cddf2c9e15600873de55259dac6b0e6'
    label: cve@mitre.org
  - url: 'https://github.com/momo-trip/poc_ffmpeg'
    label: cve@mitre.org
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-09T15:16:35.323659Z'
epss: 0.00512
epssPercentile: 0.41079
ingestedAt: '2026-09-08T21:11:12.370Z'
---

## Overview

A memory corruption vulnerability exists in FFmpeg before 8.1. The RTP encoding process. In the nal_send function in libavformat/rtpenc_h264_hevc.c, a negative size parameter (size=-3) is passed to memcpy when transmitting H.264/HEVC streams via RTP using a crafted input file. This was detected using AddressSanitizer.

## Remediation

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