SB20260918427 - Integer overflow in Linux kernel apparmor

Description

This security bulletin contains information about 1 vulnerability.

1) Integer overflow (CVE-ID: CVE-2026-90246)

CWE-ID: CWE-190 - Integer overflow

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to read out-of-bounds memory.

The vulnerability exists due to an integer overflow in the verify_tags() bounds check in AppArmor policy unpacking when loading a crafted policy blob. A local user can load a crafted AppArmor policy to read out-of-bounds memory.

With the default unprivileged_userns_apparmor_policy=1 setting, the policy-loading path is reachable from an unprivileged task in a matched-level nested user namespace.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/465946d3c560c0137e6a180ba054dddc4d049f5a
• https://git.kernel.org/stable/c/ef79a405f83993f0fda5efde371d98433f7d7a47