CVE-2026-125252 and is rated Medium severity with a CVSS score of 4.7. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Nov 13, 2026
Release Notes
CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-125252?
FFmpeg through 9.0.2 contains a memory leak vulnerability in libavcodec/vaapi_decode.c that allows attackers to exhaust memory by supplying streams with slice parse errors. Attackers can craft H.264 or other VAAPI-decoded video where later slices fail to parse on every frame, continuously leaking VA parameter and slice buffers plus driver and heap memory.