CVE-2026-58049: FFmpeg - Out-of-Bounds Write in RASC Decoder decode_dlta()
FFmpeg's RASC video decoder (decodedlta in libavcodec/rasc.c) performs 32-bit reads and writes at the row cursor before the NEXTLINE 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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-58049?
CVE-2026-58049 has a severity rating of high at 8.6.
How do I fix CVE-2026-58049?
To mitigate CVE-2026-58049, update FFmpeg to the latest version where the vulnerability has been addressed.
What software is affected by CVE-2026-58049?
CVE-2026-58049 affects the FFmpeg software specifically related to the RASC video decoder.
What are the consequences of CVE-2026-58049?
Exploitation of CVE-2026-58049 could lead to an out-of-bounds write which may corrupt memory and possibly lead to remote code execution.
What does CVE-2026-58049 relate to in FFmpeg?
CVE-2026-58049 pertains to an out-of-bounds write issue in the RASC decoder's decode_dlta function in FFmpeg.