CVE-2026-56211
HighCVSS 7.1Exploitation Probability (EPSS)
Low risk38th percentile - higher than 38% of all known CVEs
Summary
The libaom library (reference AV1 codec implementation) contains a remote code execution vulnerability. Insufficient bounds validation in the AV1 encoder's SVC layer ID control allows an attacker to supply crafted video frames that can overwrite encoder context structures.
Risk Assessment
In fork-based video processing services, an attacker can exploit this vulnerability to hijack the process and execute arbitrary code.
Recommendation
Update the libaom library to a patched version. If possible, disable SVC encoding in services processing user-supplied data.
Other vulnerabilities in libaom
See all- CVE-2026-56210High
A heap-buffer-overflow read vulnerability was found in libaom, the reference AV1 codec implementation. A missing bounds check in the SVC layer ID control function allows setting a spatial_layer_id exceeding the configured number of layers, causing an out-of-bounds heap read of approximately 40,728 bytes.
- CVE-2026-56209High
An arbitrary address write vulnerability in libaom, the reference AV1 codec implementation, allows an attacker to inject an arbitrary pointer into the cyclic refresh map field via a missing bounds check in the SVC layer ID control function. An attacker who can supply frames to a network-facing libaom encoder with SVC enabled could exploit this for denial of service or potential code execution.
- CVE-2026-56208High
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.
Original NVD description (English source)
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.