What’s Vulnerable › Vulnerabilities

CVE-2021-38171

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-08-21 · updated 2026-06-17
• Weakness: CWE-252

Description

adts_decode_extradata in libavformat/adtsenc.c in FFmpeg 4.4 does not check the init_get_bits return value, which is a necessary step because the second argument to init_get_bits can be crafted.

Affected products

• Debian Linux: 9.0, 10.0, 11.0
• FFmpeg: 4.4

References

• https://github.com/FFmpeg/FFmpeg/commit/9ffa49496d1aae4cbbb387aac28a9e061a6ab0a6
• https://lists.debian.org/debian-lts-announce/2021/11/msg00012.html
• https://patchwork.ffmpeg.org/project/ffmpeg/patch/AS8P193MB12542A86E22F8207EC971930B6F19%40AS8P193MB1254.EURP193.PROD.OUTLOOK.COM/
• https://security.gentoo.org/glsa/202312-14
• https://www.debian.org/security/2021/dsa-4990
• https://www.debian.org/security/2021/dsa-4998
• https://github.com/FFmpeg/FFmpeg/commit/9ffa49496d1aae4cbbb387aac28a9e061a6ab0a6
• https://lists.debian.org/debian-lts-announce/2021/11/msg00012.html
• https://patchwork.ffmpeg.org/project/ffmpeg/patch/AS8P193MB12542A86E22F8207EC971930B6F19%40AS8P193MB1254.EURP193.PROD.OUTLOOK.COM/
• https://security.gentoo.org/glsa/202312-14
• https://www.debian.org/security/2021/dsa-4990
• https://www.debian.org/security/2021/dsa-4998

Get alerted when CVE-2021-38171 or the next vulnerability affects your stack