Answer in brief
CVE-2026-125221 records a Medium severity (CVSS 6.8) vulnerability in FFmpeg through 9.0.2 Uncontrolled Recursion in FLAC Parser score_header(). The current sources do not mark it as known exploited. The current feed maps FFmpeg/FFmpeg (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps FFmpeg/FFmpeg (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| FFmpeg/FFmpeggeneric | >=0 <=9.0.2 | Not reported |
Published upstream
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 9, 2026
FFmpeg through 9.0.2 contains an uncontrolled recursion vulnerability in score_header() in libavcodec/flac_parser.c that allows attackers to exhaust the thread stack via crafted FLAC input. Attackers can supply a FLAC stream packed with many small valid-looking frame headers, forcing deep recursion that crashes the process during demuxing or parsing.
Quoted source text, attributed separately from HOL analysis.