What is CVE-2026-90231?

CVE-2026-90231 is a High severity Linux kernel vulnerability with a CVSS score of 8.4 out of 10, affecting Linux kernel versions from 6.7 onward and patched in 6.18.52, 7.2.6 and 7.3-rc1. CVE-2026-90231 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-90231?

CVE-2026-90231 has a CVSS score of 8.4 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N.

Is there a patch available for CVE-2026-90231?

Yes, CVE-2026-90231 has been patched. Fixed versions include 6.18.52, 7.2.6 and 7.3-rc1. If you are running Linux kernel 6.7 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-90231 actively exploited?

CVE-2026-90231 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-90231

High

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix unconfined user namespace restriction forced stack If a task is already confined by a stack the unprivileged transition restriction on unconfined is not correctly, applied. This results in an escape if two transitions through an unconfined profile can be executed. Fix this by pushing the check into the per profile label build. The check will always be done against unconfined and result in a stack of just the unconfined component when necessary.

Package Linux Kernel

Published 2026-09-17

Last modified 2026-09-18

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.4

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

Affected versions

Linux kernel versions 6.7 and later are affected. Fixed in 6.18.52, 7.2.6, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.7

Fixed in

✓ 6.18.52 6.18.x ✓ 7.2.6 7.2.x ✓ 7.3-rc1

References

3 total

Details

CVE ID CVE-2026-90231

Severity High

CVSS score 8.4 / 10

CVSS version 3.1

Published 2026-09-17

Modified 2026-09-18

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-90231?

CVE-2026-90231 is a High severity Linux kernel vulnerability with a CVSS score of 8.4 out of 10 . It affects Linux kernel versions from 6.7 onward and has been patched in 6.18.52, 7.2.6 and 7.3-rc1. CVE-2026-90231 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-90231?

CVE-2026-90231 has a CVSS score of 8.4 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N.
Is there a patch available for CVE-2026-90231?

Yes. CVE-2026-90231 has been patched. Fixed versions include 6.18.52, 7.2.6 and 7.3-rc1. If you are running Linux kernel 6.7 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-90231 actively exploited?

No. CVE-2026-90231 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.