CVE-2026-125211FFmpeg FFmpeg Out-of-bounds Read
NVD
Vulnerability Summary
FFmpeg through 9.0.2 contains an out-of-bounds read and invalid free vulnerability in aribcaption_trans_ass_subtitle() in libavcodec/libaribcaption.c that frees subtitle rectangles using region_count instead of num_rects. Attackers can supply crafted ARIB captions whose later region exceeds the 8 KiB AVBPrint limit, triggering cleanup that frees out-of-bounds pointers and corrupts the heap.
CVSS v4.0 Base Metrics — Score 7.3 (HIGH)
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NAttack VectorLocal
Attack ComplexityHigh
Attack RequirementsPresent
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)High
Integrity (Vulnerable System)High
Availability (Vulnerable System)High
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 7.0)
CVSS v3.1 Base Metrics — Score 7.0 (HIGH)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:HAttack VectorLocal
Attack ComplexityHigh
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
Affected & Patched Versions
- FFmpeg FFmpeg <= 9.0.2
- FFmpeg FFmpeg 9.0.2
What to do
Plan remediation soon. No exploitation is confirmed yet, but the severity is high.
- Check whether you run FFmpeg FFmpeg and which version.
- Update to a patched version listed above, then confirm the new version.
Timeline
- Nov 9, 2026Published
- Nov 10, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
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Set up CVE alertsExternal References
- Referencehttps://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24992
- Patchhttps://github.com/FFmpeg/FFmpeg/commit/4ec127c82678b06658e963291f272881dc878735
- Referencehttps://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/libaribcaption.c#L778
- Referencehttps://github.com/FFmpeg/FFmpeg
- Referencehttps://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-corruption-via-libaribcaption-ass-error-cleanup
Data last checked: Nov 13, 2026 21:28 UTC