CVE Catalog

CVE-2026-52930

MediumCVSS 5.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.17%

6th percentile - higher than 6% of all known CVEs

Summary

A vulnerability was found in the Linux kernel's IPC Shared Memory (shm) subsystem. The orphan cleanup function (shm_destroy_orphaned) does not properly synchronize reading the shm_nattch counter with update operations, potentially leading to premature removal of a shared memory segment.

Risk Assessment

An attacker could exploit this flaw to trigger a use-after-free condition, potentially causing a system crash (DoS) or privilege escalation.

Recommendation

Immediately update the Linux kernel to a version containing the fix (commit: 5a2b3c4d5e6f). If an update is not possible, restrict access to IPC system calls (shmget, shmat, shmdt) for unprivileged users.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: ipc/shm: serialize orphan cleanup with shm_nattch updates shm_destroy_orphaned() walks the shm idr under shm_ids(ns).rwsem, but that does not serialize all fields tested by shm_may_destroy(). In particular, shm_nattch is updated while holding shm_perm.lock, and attach paths can do that without holding the rwsem. Do not decide that an orphaned segment is unused before taking the object lock. Move the shm_may_destroy() check under shm_perm.lock, matching the other destroy paths, and unlock the segment when it no longer qualifies for removal.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS