November 14, 2026

CVE Watchtower

CVE-2026-125175FFmpeg FFmpeg

NVD

Vulnerability Summary

FFmpeg through 9.0.2 contains an information disclosure vulnerability in flashsv_decode_block() in libavcodec/flashsv.c that copies uninitialized heap memory into decoded frames when inflate output is short. Attackers can supply a crafted FLV with an FSV1 stream whose zlib block data decompresses short, then recover heap contents from the decoded or re-encoded output.
Severity Level
MEDIUM(4.8)
Published Date
Nov 9, 2026
Last Modified
Nov 10, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.13%Probability
Root Weakness (CWE)
CWE-908 ↗
See the MITRE CWE entry for the full definition of this weakness.
CVSS v4.0 Base Metrics — Score 4.8 (MEDIUM)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Attack VectorLocal
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)Low
Integrity (Vulnerable System)None
Availability (Vulnerable System)None
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 3.3)
CVSS v3.1 Base Metrics — Score 3.3 (LOW)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Attack VectorLocal
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone

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 10, 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 21:28 UTC