CVE-2026-58049
FFmpeg - Out-of-Bounds Write in RASC Decoder decode_dlta()
CVSS Score
8.6
EPSS Score
0.2%
EPSS Percentile
14th
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.
| CWE | CWE-787 |
| Vendor | ffmpeg |
| Product | ffmpeg |
| Published | Jun 28, 2026 |
| Last Updated | Aug 11, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
High
Affected Versions
FFmpeg / FFmpeg
0 ≤ bcd2c69e087a09b07cf45c6bd2428ee1ccb2925c
References
github.com: https://github.com/bikini/exploitarium/tree/main/ffmpeg-rasc-dlta-calc-poc github.com: https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/rasc.c vulncheck.com: https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-write-in-rasc-decoder-decode-dlta access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-58049 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2493952 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-58049.json access.redhat.com: https://access.redhat.com/errata/RHSA-2026:52832 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:52833 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:51180 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:43711
Credits
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