CVE-2026-89658: In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free durin
CVE-2026-89658 is a critical-severity flaw (CVSS 9.8) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during NFSv4.0 revoked-state cleanup nfs40_clean_admin_revoked() takes a stateid reference under clp->cl_lock, drops nn->client_lock, and calls nfsd4_drop_revoked_stid(), which dereferences the stateid's client through s->sc_client->cl_lock. The stateid reference does not pin the client, so a teardown racing the dropped lock can free the cli
Why this priority
- Critical severity
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.6% (top 51%) |
| CISA exploited list | No |
| Published | 2026-09-11 |
| Last modified | 2026-10-19 |
Last updated 2026-10-19 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-89658?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-89658 being exploited?
CVE-2026-89658 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-89658 affect?
CVE-2026-89658 affects affected software. Severity is critical (CVSS 9.8). In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during NFSv4.0 revoked-state cleanup nfs40_clean_admin_revoked() takes a stateid reference under clp->cl_lock, drops nn->client_lock,
How urgent is CVE-2026-89658?
Priority 57/100. Critical severity; Remotely exploitable, no login, no user action; On your watchlist