Vulnerability in FFmpeg

[ Description ]Official description

FFmpeg 4.4 through 9.0.2 contains a use of uninitialized variable vulnerability in the CDXL decoder that leaks stack memory into decoded pixels via unfilled HAM palette entries. Attackers can craft a type-0 CDXL file whose HAM pixels select unfilled new_palette entries in cdxl_decode_ham8() or cdxl_decode_ham6(), exposing stack bytes and pointer fragments in the BGR24 output.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund1 Nov 2026WID-SEC-2026-4282

  ffmpeg: Multiple vulnerabilities allow information disclosure Translated from German

  CVE-2026-120246CVE-2026-120210CVE-2026-120243+3 more CVEs

[ References ]References

• code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24856
• github.com/FFmpeg/FFmpeg
• github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/cdxl.c
• github.com/FFmpeg/FFmpeg/commit/47313ad3f9f33b892384b976fb7c09b3c85fd74e
• www.vulncheck.com/advisories/ffmpeg-4.4-through-9.0.2-uninitialized-memory-disclosure-v…