CVE-2026-70629
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a…
Does this matter?
Lower severity and a low EPSS score (0.13%). Track it; it rarely justifies an emergency change on its own.
Description
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a compressed tile that decompresses fewer bytes than the declared tile geometry requires. When rscc_decode_frame() calls av_image_copy_plane() without validating the decompressed byte count against the tile dimensions, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame, potentially exposing data from prior heap allocations or previous decoded frames in persistent decoding services.
- CVSS 4.0
- 6.8 MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-908
- Affected
- ffmpeg/ffmpeg
- Source
- disclosure@vulncheck.com
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/533a6198505edd1379e1cd722852350ae4a85accPatch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/a5fe21a1a410a680fe93c33b0dd696b7e1c3aea4Patch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/cd1f545cf27ba08f6f5b31b1e92665d7874d4fd7Patch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23895Issue Tracking, Patch
- https://www.vulncheck.com/advisories/ffmpeg-uninitialized-heap-memory-read-in-rscc-decoderPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.