A race condition that leads to a use‑after‑free occurs in the blk‑cgroup subsystem of the Linux kernel when multiple block cgroup groups are released simultaneously. The first group’s __blkcg_rstat_flush() removes another group’s iostat entries while that entry is still being accessed, causing a kernel memory corruption. A local attacker could exploit this flaw to execute arbitrary code at ring 0, leading to full system compromise or privilege escalation.

All systems running Linux kernel 6.4 or the 6.4 release candidate rc7 that contain the unpatched blk‑cgroup code are potentially affected. The specific kernel releases are not listed in the CVE, so administrators should verify whether their running kernel incorporates the commits referenced in the CVE materials. The vulnerability affects the core Linux kernel and is not tied to a particular distribution.

The CVSS score of 7.8 indicates high severity. The EPSS score of < 1% suggests that, as of the latest data, active exploitation is unlikely, and the flaw is not listed in the CISA KEV catalog. Exploitation requires local access or an environment where the attacker can execute code on the host, such as an insider or a process with elevated privileges. Because it is a kernel‑level flaw, successful exploitation would provide unrestricted control over the affected system. Based on the description, the likely attack vector is local code execution that triggers concurrent release of multiple blk‑cgroup groups.