libaom EUVD-2026-38047

A remote code execution vulnerability was found in libaom, the reference AV1 codec implementation. Insufficient bounds validation in the AV1 encoder's SVC (Scalable Video Coding) layer ID control allows an attacker to supply crafted video frame pixels that overlap with internal encoder layer context structures. In fork-based video processing services, an attacker can use this to hijack the cyclic refresh map pointer, brute-force the process base address via a crash oracle, and redirect control flow to achieve arbitrary command execution. Exploitation requires the target service to use libaom with SVC encoding enabled and accept attacker-supplied video frames.

The vulnerable component is libaom, the AOMedia reference AV1 codec, specifically the AV1 encoder's SVC layer-ID control path. Exact fixed versions are not enumerated in the provided data; the upstream fix is the aomedia commit a93ba0ffaa (https://aomedia.googlesource.com/aom/+/a93ba0ffaa). Downstream tracking is available via Red Hat (https://access.redhat.com/security/cve/CVE-2026-56211 and Bugzilla 2490802 at https://bugzilla.redhat.com/show_bug.cgi?id=2490802) and Chromium issue 503993985 (https://issues.chromium.org/issues/503993985), indicating Red Hat Enterprise Linux libaom packages and Chromium/Chrome's bundled libaom are affected pending vendor-specific package versions. No CPE strings were supplied, so precise affected version ranges for distros and embedders must be confirmed against each vendor advisory.