Linux kernel vulnerability in nfsd can cause kernel-level use-after-free across many servers; widespread impact on infrastructure warrants broad distribution.
CVE-2026-89669
Linux kernel nfsd race → use-after-free enabling kernel crash or RCE
Is CVE-2026-89669 being exploited?
Not confirmed. CVE-2026-89669 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 0.68% probability of exploitation in the next 30 days.
How severe is CVE-2026-89669?
CVE-2026-89669 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-2026-89669?
Yes. A fix has been recorded for CVE-2026-89669. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89669 affect?
CVE-2026-89669 affects Linux kernel (nfsd - NFS server). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89669?
Apply kernel updates with the nfsd fix and restart NFS services promptly.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated NFS client can trigger use-after-free in nfsd, causing kernel panic, privilege escalation, or potential remote code execution.
Immediate action required
- affected>= 624322f1adc58acd0b69f77a6ddc764207e97241 and < e08a3dcaca0505f861e344a387f37f94d95dbdc2
- affected>= 624322f1adc58acd0b69f77a6ddc764207e97241 and < a4d7fedcaaf33e60a01e53eafca9041ef966212f
- affected>= 624322f1adc58acd0b69f77a6ddc764207e97241 and < 4cdef96892f4fa6e70c405b6e8f2fd6972f3b64b
- affected>= 624322f1adc58acd0b69f77a6ddc764207e97241 and < 129643893b79f8a3c6b72045f933fbab5ee424ca
- affected5.6
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.