Kernel-level RCE in the Linux NFS server affects widely deployed Linux systems and can lead to remote kernel code execution or outage; impacts core infrastructure.
CVE-2026-89712
Linux kernel nfsd use-after-free allows remote code execution
Is CVE-2026-89712 being exploited?
Not confirmed. CVE-2026-89712 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 0.70% probability of exploitation in the next 30 days.
How severe is CVE-2026-89712?
CVE-2026-89712 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-2026-89712?
Yes. A fix has been recorded for CVE-2026-89712. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89712 affect?
CVE-2026-89712 affects Linux kernel (nfsd/NFS server), Linux distributions running NFS server (pre-fix kernels). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89712?
Apply vendor kernel updates for NFS servers and restart affected hosts/services
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution or kernel crash via nfsd use-after-free during mount expiry; attacker can execute code in kernel context or cause DoS.
Immediate action required
- affected>= f4e44b393389c77958f7c58bf4415032b4cda15b and < 77de363d9a1c8cd35f20482782c612cda085791a
- affected>= f4e44b393389c77958f7c58bf4415032b4cda15b and < 4ed8d2317aef21cc2a9e5a55d6b59860b4b151a8
- affected>= f4e44b393389c77958f7c58bf4415032b4cda15b and < 7377fa964b8aaf47cb04e5efcc4c82d15e8c2ce9
- affected>= f4e44b393389c77958f7c58bf4415032b4cda15b and < 036c1b182f4da65363e79ec0ac276edc6b7296e5
- affecteda4bc287943f5695209ff36bdc89f17b48d68fae7
- affected>= 5.10.220 and < 5.11
- affected5.14
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.