Affects the Linux kernel NFS server (nfsd) used widely across enterprises; can disrupt shared file services and cause outages, making it broadly impactful.
CVE-2026-89681
Linux kernel nfsd race leaks layout stateid, risking NFS server resource exhaustion.
Is CVE-2026-89681 being exploited?
Not confirmed. CVE-2026-89681 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 0.38% probability of exploitation in the next 30 days.
How severe is CVE-2026-89681?
CVE-2026-89681 is rated Critical with a CVSS score of 9.8. 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-2026-89681?
Yes. A fix has been recorded for CVE-2026-89681. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89681 affect?
CVE-2026-89681 affects Linux kernel (nfsd / NFS server), Major Linux distributions' kernels. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89681?
Apply vendor kernel security updates and reboot NFS servers.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote NFS clients can trigger a double-reference that leaks layout stateid, potentially leading to resource exhaustion and DoS of NFS servers.
Immediate action required
- affected>= f52792f484ba2316853736856dde19b7e7458861 and < a278d361e0e8f242211891193d56483a7a9f47a8
- affected>= f52792f484ba2316853736856dde19b7e7458861 and < 8580571227451384399b3fa53fcde19848c48e5a
- affected7.1
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.