CVE-2026-56208

high

Description

A heap buffer overflow vulnerability was found in libaom, the reference AV1 codec implementation. A flaw in the AV1 encoder's Look-Ahead Processing (LAP) mode causes the first-pass stats ring buffer wrap-around guard to be bypassed when g_lag_in_frames is set to 1 or higher. This results in a 232-byte out-of-bounds write on every encoded frame after the second, corrupting adjacent heap objects. An attacker who can influence encoder configuration in a transcoding service or WebRTC session could exploit this to cause a denial of service (process crash) or potentially achieve code execution.

References

https://issues.chromium.org/issues/504317456

https://bugzilla.redhat.com/show_bug.cgi?id=2490799

https://aomedia.googlesource.com/aom/+/243f8ae84b

https://access.redhat.com/security/cve/CVE-2026-56208

Details

Source: Mitre, NVD

Published: 2026-06-19

Updated: 2026-06-19

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:C

Severity: High

CVSS v3

Base Score: 7.6

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H

Severity: High