CVE-2026-89712
A critical bug in the Linux kernel’s NFS server could let an attacker trigger a use‑after‑free, potentially enabling arbitrary code execution. The flaw occurs when the kernel walks a list of source mounts while releasing a lock, allowing a concurrent thread to free an item that the walk still references. The issue has been fixed in a kernel patch.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Linux kernel, specifically the NFS server (nfsd) component. Users running affected kernel versions that have not applied the patch are at risk.
Real-world impact
An attacker could trigger a use‑after‑free in the NFS server, potentially allowing them to execute arbitrary code with kernel privileges, leading to full system compromise.
Why this severity
The CVSS score of 9.8 reflects the high impact (confidentiality, integrity, availability) and the fact that the vulnerability can be exploited remotely without authentication or user interaction.
What to do about it
- 01Upgrade the Linux kernel to a version that includes the fix for CVE-2026-89712.
NVD description indicates the issue has been resolved.
Timeline
- Sep 11, 2026 · 2d agoPublishedDisclosed and added to the National Vulnerability Database.
- Sep 13, 2026 · 6h agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.