# CVE-2026-124031: GPAC through 26.07.0 Type Confusion via drawable_get_aspect_2d_mpeg4


- **Severity:** Medium 6.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 6 Nov 2026
- **Updated:** 9 Nov 2026
- **Also known as:** GHSA-f589-88mc-5jx5, UBUNTU-CVE-2026-124031

## What is CVE-2026-124031?

CVE-2026-124031 is a medium-severity vulnerability in gpac, published on 6 Nov 2026. 

### Official description

GPAC through 26.07.0 contains a type confusion vulnerability in drawable_get_aspect_2d_mpeg4() and TraverseShape() that casts a Shape's appearance node to M_Appearance without checking its node tag. Attackers can supply a crafted XMT file placing another node type, such as Conditional, in the appearance field to trigger an invalid memory read and crash MP4Box.

Weakness: CWE-843 (Access of Resource Using Incompatible Type)

## Which versions are affected by CVE-2026-124031?


## How do I fix CVE-2026-124031?

No fix has been published for CVE-2026-124031 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-124031 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-124031 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-124031 and fix it if it is affected.

What it is: CVE-2026-124031 is a medium-severity vulnerability in gpac, published on 6 Nov 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-124031 exists.

Affected product: gpac. 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-2026-124031/ (Markdown: https://insights.sbomify.com/CVE-2026-124031/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-124031
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-124031
- OSV: https://osv.dev/vulnerability/CVE-2026-124031

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-124031/
Summaries are generated and may contain mistakes; the official description above is the record.