# CVE-2026-10037: Sandbox Escape in Ubuntu OpenJDK Packages via xdg-desktop-portal


- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 8 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** GHSA-xg8h-3f4m-39v6, UBUNTU-CVE-2026-10037, USN-8518-1

## What is CVE-2026-10037?

CVE-2026-10037 is a high-severity vulnerability in Canonical Ubuntu, published on 8 Jul 2026. 

### Official description

A sandbox escape vulnerability exists in the OpenJDK packages provided in Ubuntu. The .jar MIME handlers installed by these packages execute files marked as executable when the mailcap package is installed. A compromised or malicious sandboxed application with access to the OpenURI portal via xdg-desktop-portal-gtk can write a malicious .jar file to the host file system, set its executable bit, and trigger the handler to execute arbitrary code outside of the sandbox environment.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-10037?


## How do I fix CVE-2026-10037?

Upgrade to a fixed version.

## Is CVE-2026-10037 being exploited?

There is no known exploitation of CVE-2026-10037 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10037 and fix it if it is affected.

What it is: CVE-2026-10037 is a high-severity vulnerability in Canonical Ubuntu, published on 8 Jul 2026. 
Exploitation: There is no known exploitation of CVE-2026-10037 in the wild and no public exploit code.

Affected product: Canonical Ubuntu. 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-2026-10037/ (Markdown: https://insights.sbomify.com/CVE-2026-10037/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10037
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10037
- OSV: https://osv.dev/vulnerability/CVE-2026-10037

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10037/
Summaries are generated and may contain mistakes; the official description above is the record.