CVE-2023-53629
A critical flaw in the Linux kernel’s Distributed Lock Manager (DLM) allows a use‑after‑free error that can be triggered when processing DLM messages in a softirq context. The bug could let an attacker run arbitrary code with kernel privileges. A patch has been released to fix the issue.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Linux kernel users on any version that includes the DLM subsystem and has not yet applied the patch. This includes most modern Linux distributions that ship a kernel with DLM support.
Real-world impact
An attacker could exploit the use‑after‑free to execute arbitrary code with kernel privileges, potentially taking full control of the affected system.
Why this severity
The CVSS score of 9.8 reflects that the vulnerability can be exploited remotely without authentication or user interaction, and it provides complete compromise of confidentiality, integrity, and availability.
What to do about it
- 01Upgrade your Linux kernel to a version that includes the "dlm: fix use after free in midcomms" patch.
- 02Restart the system or reload the kernel to activate the new version.
NVD-referenced vendor advisory
Timeline
- Oct 7, 2025 · Oct 7, 2025PublishedDisclosed and added to the National Vulnerability Database.
- Aug 4, 2026 · 1d agoAdvisory updatedThe NVD record was last revised.
- Aug 4, 2026 · 1d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.