UBUNTU-CVE-2026-120246

Dashboard / Vulnerabilities / UBUNTU-CVE-2026-120246

UBUNTU-CVE-2026-120246

Summary:

Details: 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.

References: https://ubuntu.com/security/CVE-2026-120246, https://www.cve.org/CVERecord?id=CVE-2026-120246, https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24856, https://github.com/FFmpeg/FFmpeg, https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/cdxl.c#L226-L229, https://github.com/FFmpeg/FFmpeg/commit/47313ad3f9f33b892384b976fb7c09b3c85fd74e, https://www.vulncheck.com/advisories/ffmpeg-4.4-through-9.0.2-uninitialized-memory-disclosure-via-cdxl-ham-decoder