CVE-2026-120246mediumCWE-457

CVE-2026-120246: medium-severity vulnerability in FFmpeg

FFmpeg 4.4 through 9.0.2 Uninitialized Memory Disclosure via CDXL HAM Decoder

Published

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.8epss 0.1%
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.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
FFmpeg · FFmpeg
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