CVE-2026-58049highCWE-787

CVE-2026-58049: high-severity vulnerability in FFmpeg

FFmpeg - Out-of-Bounds Write in RASC Decoder decode_dlta()

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41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 8.8epss 0.5%
FFmpeg's RASC video decoder (decode_dlta in libavcodec/rasc.c) performs 32-bit reads and writes at the row cursor before the NEXT_LINE row-boundary check and validates the DLTA region in pixel rather than byte units, so a DLTA run on a PAL8 frame can access several bytes past the row allocation. A crafted media stream using the RASC FourCC, decoded by libavcodec, triggers a bitstream-controlled out-of-bounds heap write and adjacent out-of-bounds read, leading to memory corruption.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
FFmpeg · FFmpeg
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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