CVE-2026-125256
FFmpeg through 9.0.2 Heap Buffer Overflow via RISC-V Vector diff_bytes Routine
FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in ff_llvidenc_diff_bytes_rvv() that allows attackers to corrupt heap memory by triggering negative length values in the Huffyuv encoder. Attackers can supply RGB video narrower than 8 or 16 pixels for huffyuv transcoding on RVV-enabled RISC-V builds, causing writes past the encoder's temp buffer.
Public vulnerability details
- Record state
- Published
- Published (UTC)
- Last updated (UTC)
- Assigned by
- VulnCheck
- CVSS score
- 7.3 (CVSS v4.0, from VulnCheck)
- Severity
- HIGH
- CISA KEV
- No KEV entry in this record. This does not show that the CVE is absent from the KEV catalog.
- Additional data from
- None
FHE assessment
No FHE assessment is available in this application yet. This does not mean FHE cannot mitigate an impact of this CVE.
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25573 (VulnCheck)
- Patch Commit (VulnCheck)
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/riscv/llvidencdsp_rvv.S#L26 (VulnCheck)
- https://github.com/FFmpeg/FFmpeg (VulnCheck)
- VulnCheck Advisory: FFmpeg through 9.0.2 Heap Buffer Overflow via RISC-V Vector diff_bytes Routine (VulnCheck)
Source
CVE JSON 5.2 record from the CVE List archive 2026-11-09_delta_CVEs_at_end_of_day.zip, which covers changes through . Imported .