Linux kernel NFS server vulnerability affects widely deployed kernels and can cause kernel compromise or outages across organizations.
CVE-2026-89675
Use-after-free in Linux nfsd enabling kernel memory corruption (crash/RCE).
Is CVE-2026-89675 being exploited?
Not confirmed. CVE-2026-89675 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 0.45% probability of exploitation in the next 30 days.
How severe is CVE-2026-89675?
CVE-2026-89675 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-2026-89675?
Yes. A fix has been recorded for CVE-2026-89675. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89675 affect?
CVE-2026-89675 affects Linux kernel (nfsd / NFS server), Major Linux distributions' kernels running NFS server. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89675?
Apply vendor kernel updates and restart NFS services immediately.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote (authenticated) NFS client can trigger a kernel use-after-free, leading to crashes, escalation to root or potential arbitrary kernel code execution.
Immediate action required
- affected>= e0639dc5805a9d4faaa2c07ad98fa853b9529dd3 and < 9031493ef7369d5c59c4bacc96f0c85965f09a98
- affected>= e0639dc5805a9d4faaa2c07ad98fa853b9529dd3 and < a385cf5e016b748babf94cc664e43a26e17db117
- affected>= e0639dc5805a9d4faaa2c07ad98fa853b9529dd3 and < 62c0f6eaf050bb9284c1f9cac6ed1770092e6b95
- affected4.20
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.