Skip to main content
VulnerabilityPublished

CVE-2026-125221: FFmpeg · Uncontrolled Recursion

Affects FFmpegSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 6.8 Medium.

Data as of 9 Nov 2026, 20:21 UTC

CVSS 4.0 base score
6.8Medium
How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none
CVSS scores by source
CNA (VulnCheck)CVSS 4.06.8
CNA (VulnCheck)CVSS 3.15.5
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 9 Nov 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 9 Nov 2026.

What to do

Affected software

ProductAffectedFixed in
FFmpegFFmpegAffected
  • <=9.0.2
Fixed in–
GitHubFFmpegpkg:github/FFmpegOther threatsAffected
  • <=9.0.2
Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Until a fix is available, avoid processing untrusted or malformed FLAC streams with vulnerable FFmpeg versions to mitigate risk.

Description

CVE-2026-125221 is a vulnerability in FFmpeg versions up to 9.0.2 involving uncontrolled recursion in the score_header() function within libavcodec/flac_parser.c. This flaw allows an attacker to craft a FLAC audio stream with many small valid-looking frame headers, causing deep recursion that exhausts the thread stack and crashes the process during demuxing or parsing.

References

Community reviews

Loading reviews…