CVE-2026-63827: Linux kernel · apparmor: fix use-after-free in rawdata dedup loop
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 12 Nov 2026, 17:35 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 19 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Linux Linux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in the Linux kernel versions listed as affected. Users and administrators should upgrade to the fixed kernel versions to remediate this vulnerability. No additional mitigations are necessary beyond applying the official patches.
Description
CVE-2026-63827 is a use-after-free vulnerability in the AppArmor component of the Linux kernel. It occurs in the rawdata deduplication loop where a reference count can be incorrectly incremented on an already freed object, leading to potential memory corruption. This flaw affects specific Linux kernel versions and has been fixed by introducing a safer reference count check to skip dying entries during deduplication.
References
- git.kernel.org/stable/c/643221da57dbb1a8fd800610331cf1ec27969f71 (opens in a new tab)
- git.kernel.org/stable/c/b17f0c59cc1525765625cf07d0391b7f9c1ed7e5 (opens in a new tab)
- git.kernel.org/stable/c/a7a2890028f16e5b0af0bb005d80fcb32559cca3 (opens in a new tab)
- git.kernel.org/stable/c/15fd83a1e42ede15070968806bb6c8b1a5170688 (opens in a new tab)
- git.kernel.org/stable/c/ce261a20b41db522e320a41bbf1292bf85af66df (opens in a new tab)
- git.kernel.org/stable/c/c3ca2631073b2cef06824fd2bfc452ff7a1023de (opens in a new tab)
- git.kernel.org/stable/c/5e34fa9f6f7cd688ae153fff13139a5cf2d42339 (opens in a new tab)
- git.kernel.org/stable/c/6f060496d03e4dc560a40f73770bd08335cb7a27 (opens in a new tab)