Use After Free Affecting ffmpeg package, versions <7:4.4-5


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.92% (56th percentile)

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  • Snyk IDSNYK-ECHOLATEST-FFMPEG-18234657
  • published23 Jul 2026
  • disclosed10 Aug 2021

Introduced: 10 Aug 2021

CVE-2020-21697  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Echo:latest ffmpeg to version 7:4.4-5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream ffmpeg package and not the ffmpeg package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

A heap-use-after-free in the mpeg_mux_write_packet function in libavformat/mpegenc.c of FFmpeg 4.2 allows to cause a denial of service (DOS) via a crafted avi file.

CVSS Base Scores

version 3.1