CVE-2026-23405

apparmor: fix: limit the number of levels of policy namespaces

State: Published
Severity: Not scored
Published: Apr 1, 2026
Updated: May 11, 2026
Reserved: Jan 13, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

apparmor: fix: limit the number of levels of policy namespaces

Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource.

Hard cap policy namespaces to the same depth as user namespaces.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 6b396cc2f0365e684fc1d3547d18ef79fcee225dAffected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3Affected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before b1226e37eb3754d389721c135db6107db94c7a72Affected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2eAffected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 853ce31ca72097d23991a06876a2ccb5cb64b603Affected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before d42b2b6bb77ca40ee34ab74ad79305840b5f315dAffected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 7b6495ead2c611647f6b11441a852324e3eb8616Affected c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 306039414932c80f8420695a24d4fe10c84ccfb2Affected
LinuxLinux	2.6.36Affected before 2.6.36Not affected 5.10.253 through 5.10.Not affected 5.15.203 through 5.15.Not affected 6.1.169 through 6.1.Not affected 6.6.130 through 6.6.Not affected 6.12.77 through 6.12.Not affected 6.18.18 through 6.18.Not affected 6.19.8 through 6.19.*Not affected 7.0 and laterNot affected

Product

Versions

LinuxLinux

c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 6b396cc2f0365e684fc1d3547d18ef79fcee225dAffected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3Affected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before b1226e37eb3754d389721c135db6107db94c7a72Affected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2eAffected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 853ce31ca72097d23991a06876a2ccb5cb64b603Affected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before d42b2b6bb77ca40ee34ab74ad79305840b5f315dAffected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 7b6495ead2c611647f6b11441a852324e3eb8616Affected
c88d4c7b049e87998ac0a9f455aa545cc895ef92 to before 306039414932c80f8420695a24d4fe10c84ccfb2Affected

LinuxLinux

2.6.36Affected
before 2.6.36Not affected
5.10.253 through 5.10.*Not affected
5.15.203 through 5.15.*Not affected
6.1.169 through 6.1.*Not affected
6.6.130 through 6.6.*Not affected
6.12.77 through 6.12.*Not affected
6.18.18 through 6.18.*Not affected
6.19.8 through 6.19.*Not affected
7.0 and laterNot affected

References

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