# CVE-2026-90827: GPAC MP4Box base_scenegraph.c gf_node_deactivate_ex use after free

> A local attacker can exploit a use-after-free flaw in GPAC MP4Box to potentially execute arbitrary code or cause a denial of service.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-gr8c-qjcx-xc56, UBUNTU-CVE-2026-90827

## What is CVE-2026-90827?

CVE-2026-90827 is a medium-severity use after free vulnerability in GPAC, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was identified in GPAC 26.07.0. This affects the function gf_node_deactivate_ex of the file scenegraph/base_scenegraph.c of the component MP4Box. Such manipulation leads to use after free. The attack must be carried out locally. The exploit is publicly available and might be used. Upgrading to version abi-16.23 is able to mitigate this issue. The name of the patch is 49dee5cad329cfed310c1682703df7daa47df31a. You should upgrade the affected component.

Weakness: CWE-416 (Use After Free), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-90827?


## How do I fix CVE-2026-90827?

No fix has been published for CVE-2026-90827 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-90827 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-90827 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90827 and fix it if it is affected.

What it is: CVE-2026-90827 is a medium-severity use after free vulnerability in GPAC, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-90827 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-2026-90827/ (Markdown: https://insights.sbomify.com/CVE-2026-90827/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90827
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90827
- OSV: https://osv.dev/vulnerability/CVE-2026-90827

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90827/
Summaries are generated and may contain mistakes; the official description above is the record.