November 13, 2026

CVE Watchtower

CVE-2026-125269FFmpeg FFmpeg Double Free

NVD

Vulnerability Summary

FFmpeg through 9.0.2 contains a double free vulnerability in libavcodec/cbs_sei.c where cbs_sei_delete_message() leaves a stale extension_data reference that ff_cbs_sei_add_message() reuses. Attackers can supply a crafted H.264 stream with a display orientation SEI message followed by payload extension data, processed by h264_metadata with display_orientation=insert, to corrupt heap memory.
Severity Level
HIGH(7.3)
Published Date
Nov 9, 2026
Last Modified
Nov 9, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.13%Probability
Root Weakness (CWE)
CWE-415: Double Free ↗
The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations.
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:N
Attack 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:H
Attack VectorLocal
Attack ComplexityHigh
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

Affected & Patched Versions

Affected Versions
  • FFmpeg FFmpeg <= 9.0.2
Patched Versions
  • FFmpeg FFmpeg 9.0.2

What to do

Plan remediation soon. No exploitation is confirmed yet, but the severity is high.

  1. Check whether you run FFmpeg FFmpeg and which version.
  2. Update to a patched version listed above, then confirm the new version.

Timeline

  • Nov 9, 2026Published
  • Nov 9, 2026Record last modified

Score, severity and exploitation changes are tracked from the day Watchtower started logging them.

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External References

Data last checked: Nov 13, 2026 19:14 UTC