Linux kernel vulnerability in nfsd/lockd can crash kernels or enable local privilege escalation on NFS servers; affects widely deployed Linux server infrastructure.
CVE-2026-89709
Linux kernel NFS lockd use-after-free allows kernel crash or local privilege escalation
Is CVE-2026-89709 being exploited?
Not confirmed. CVE-2026-89709 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.33% probability of exploitation in the next 30 days.
How severe is CVE-2026-89709?
CVE-2026-89709 is rated High with a CVSS score of 8.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-89709?
Yes. A fix has been recorded for CVE-2026-89709. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89709 affect?
CVE-2026-89709 affects Linux kernel (nfsd/lockd), Linux distributions shipping nfsd as a module, NFS server hosts. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89709?
Apply vendor/stable kernel updates and restart NFS services immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Kernel use-after-free in nfsd/lockd may cause kernel panic (DoS) or local privilege escalation by reusing freed module text.
Patch when possible
- affected>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 3c461a1820088fb5889d73a6522369bde45527a9
- affected>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 641e5e20852359b8c31149be4598884e30652f60
- affected2.6.12
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.