SB2026072110 - Use-after-free in Linux kernel apparmor
Published: July 21, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-63827)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in aa_replace_profiles() during rawdata_list deduplication when processing policy replacement operations. A local user can trigger AppArmor profile replacement with crafted timing to cause a denial of service.
The issue occurs because entries can remain on the rawdata list after their profile reference count has reached zero and before deferred cleanup runs.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/15fd83a1e42ede15070968806bb6c8b1a5170688
- https://git.kernel.org/stable/c/5e34fa9f6f7cd688ae153fff13139a5cf2d42339
- https://git.kernel.org/stable/c/6f060496d03e4dc560a40f73770bd08335cb7a27
- https://git.kernel.org/stable/c/a7a2890028f16e5b0af0bb005d80fcb32559cca3
- https://git.kernel.org/stable/c/c3ca2631073b2cef06824fd2bfc452ff7a1023de
- https://git.kernel.org/stable/c/ce261a20b41db522e320a41bbf1292bf85af66df