CVE-2026-52991

A flaw was found in the Linux kernel's Pressure Stall Information (PSI) subsystem. A race condition exists between the file release and pressure write operations, specifically concerning the priv member of struct kernfs_open_file. This can lead to a use-after-free vulnerability or a NULL dereference, potentially causing system instability or a denial of service. The issue arises when the priv member is deallocated during a cgroup file release while a pressure write operation attempts to access it, or when it becomes NULL before being accessed.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.