The Linux kernel SELinux module had a flaw in its per-task avdcache implementation, which incorrectly saved and reused the audited vector computed by avc_audit_required() instead of recomputing it based on the current permission request. This led to some permission checks not being audited, potentially missing audit records for certain denied or allowed operations, such as directory write checks after a cached directory search check. This vulnerability has been fixed by ensuring the audit vector is recomputed correctly to reflect the current permission context.

The vulnerability results in incomplete auditing of SELinux permission checks, which could hinder security monitoring and forensic investigations by missing audit logs for some permission denials or allowances. There is no direct impact on confidentiality or integrity of the system, but the availability impact is rated high due to potential audit reliability degradation.

A fix for this vulnerability has been implemented in the Linux kernel. Users should apply the official kernel updates that include the corrected SELinux avdcache auditing behavior. Since this is a kernel-level fix, updating to the patched kernel version is the recommended remediation. Patch status is not explicitly confirmed in the provided data; users should consult their Linux distribution vendor advisories for the exact fixed versions and update instructions.