CVE-2026-75145

FFmpeg before commit b4c199c contains an incorrect integer narrowing conversion in the AV1 RTP packetizer (libavformat/rtpenc_av1.c). The OBU size is cast to long before comparison against the remaining frame size. On targets where long is 32 bits, including 64-bit Windows, sufficiently large OBU size values are sign-flipped by the narrowing cast, producing a negative value that passes the payload size check. This allows an oversized OBU to bypass the safety bound on affected platforms, leading to out-of-bounds memory access when the oversized value is subsequently used as a copy length.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/b4c199c5906ff53368926c2a5839881f41957e7f
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24090
https://www.vulncheck.com/advisories/ffmpeg-integer-narrowing-conversion-oob-memory-access-in-av1-rtp-packetizer

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 17:21

Updated : 2026-08-31 20:37

NVD link : CVE-2026-75145

Mitre link : CVE-2026-75145

CVE.ORG link : CVE-2026-75145

JSON object : View

Products Affected

No product.

CWE

CWE-681

Incorrect Conversion between Numeric Types

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