November 13, 2026

CVE Watchtower

CVE-2026-125253FFmpeg FFmpeg Integer Overflow or Wraparound

NVD

Vulnerability Summary

FFmpeg through 9.0.2 contains an integer overflow in cbs_vp9_split_fragment() in libavcodec/cbs_vp9.c that wraps the superframe size check on 32-bit builds. Attackers can supply a crafted VP9 packet with a forged superframe index containing near-2^32 frame sizes, causing out-of-bounds reads that crash 32-bit applications.
Severity Level
MEDIUM(5.8)
Published Date
Nov 9, 2026
Last Modified
Nov 9, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.12%Probability
Root Weakness (CWE)
CWE-190: Integer Overflow or Wraparound ↗
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes the resulting value will always be larger than the original.
CVSS v4.0 Base Metrics — Score 5.8 (MEDIUM)
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Attack VectorLocal
Attack ComplexityHigh
Attack RequirementsPresent
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)Low
Integrity (Vulnerable System)None
Availability (Vulnerable System)High
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 5.3)
CVSS v3.1 Base Metrics — Score 5.3 (MEDIUM)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:H
Attack VectorLocal
Attack ComplexityHigh
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityHigh

Affected & Patched Versions

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

What to do

Fix it during your normal patch cycle. No exploitation is confirmed yet.

  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.

Get notified about new FFmpeg FFmpeg CVEsYou are reading CVE-2026-125253. Get an email when KEV listings, exploits or new CVEs match your stack.
Set up CVE alerts

External References

Data last checked: Nov 13, 2026 17:13 UTC