# CVE-2026-56211: Libaom: libaom: remote code execution via svc layer context handling with attacker-controlled frames

> Remote attackers can execute arbitrary code by sending crafted video frames to services using libaom with SVC encoding enabled.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 19 Jun 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-56211, ECHO-5509-692b-aa69, GHSA-qr4p-j2pf-4w4x, ROOT-OS-DEBIAN-11-CVE-2026-56211, UBUNTU-CVE-2026-56211

## What is CVE-2026-56211?

CVE-2026-56211 is a high-severity memory corruption vulnerability in Red Hat AI Inference Server, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

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.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-56211?


## How do I fix CVE-2026-56211?

Apply the vendor's patch.

## Is CVE-2026-56211 being exploited?

There is no known exploitation of CVE-2026-56211 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-56211 and fix it if it is affected.

What it is: CVE-2026-56211 is a high-severity memory corruption vulnerability in Red Hat AI Inference Server, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-56211 in the wild and no public exploit code.

Affected product: Red Hat AI Inference Server. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-56211/ (Markdown: https://insights.sbomify.com/CVE-2026-56211/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-56211
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-56211
- OSV: https://osv.dev/vulnerability/CVE-2026-56211

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-56211/
Summaries are generated and may contain mistakes; the official description above is the record.