# apparmor: fix unconfined user namespace restriction forced stack

CVE record · `CVE-2026-90231`

- **Identifiers:** `CVE-2026-90231`
- **State:** Confirmed
- **Severity:** CVSS 8.4 High
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 17 Sept 2026
- **Updated:** 21 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 17 Sept 2026, 16:07 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

## Affected products, as the CNA wrote them

- Vendor: Linux. Product: Linux.
  - affected: `2d9da9b188b8cd3b579d7ef5ba5d334be9dd38fc to before fdd341654471cae4fbd9635d32b848cd0c8bc437` (git)
  - affected: `2d9da9b188b8cd3b579d7ef5ba5d334be9dd38fc to before 7d1099b86356df81c379159bfb8a598aaf83ce81` (git)
  - affected: `2d9da9b188b8cd3b579d7ef5ba5d334be9dd38fc to before 7da0bdf0610f6d35bbb061536a47fc41646306f0` (git)
  - affected: `2d9da9b188b8cd3b579d7ef5ba5d334be9dd38fc to before 08c2f7c8d4b1434cfae006f3daf4d1bce330b57b` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `6.7`
  - unaffected: `before 6.7` (semver)
  - unaffected: `6.12.114 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.52 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.6 to 7.2.*, inclusive` (semver)
  - unaffected: `7.3 to *, inclusive` (original_commit_for_fix)
  - Other versions: affected

## Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

## Severity and exploitation

- 8.4 High, CVSS 3.1: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N`, from CNA (Linux)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0016, the 5th percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the CVE Program, published 17 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-90231](https://www.cve.org/CVERecord?id=CVE-2026-90231)
- [NVD: CVE-2026-90231](https://nvd.nist.gov/vuln/detail/CVE-2026-90231)

### References from the CNA

- <https://git.kernel.org/stable/c/fdd341654471cae4fbd9635d32b848cd0c8bc437>
- <https://git.kernel.org/stable/c/7d1099b86356df81c379159bfb8a598aaf83ce81>
- <https://git.kernel.org/stable/c/7da0bdf0610f6d35bbb061536a47fc41646306f0>
- <https://git.kernel.org/stable/c/08c2f7c8d4b1434cfae006f3daf4d1bce330b57b>

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.

## Check whether this affects you

This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it. Compare the affected versions above with what you run.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), `get_advisory` returns this record and `search_advisories` finds related ones. Setup: <https://agentprime.io/mcp.md>
- As JSON: <https://api.agentprime.io/v1/advisories/CVE-2026-90231>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-90231/>. Everything for agents: <https://agentprime.io/llms.txt>.