CVE-2026-89686High· 7.0▾ TwilightA flaw was found in the Linux kernel's Network File System Daemon (nfsd) for NFSv4 layouts. A race condition allows a remote attacker to trigger a kernel panic, leading to a Denial of Service (DoS). This occurs when the `nfsd4_alloc_layout…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 38.5 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 12.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CSAF
0.2%
0.2% → 0.7%
— → 5.3
none → medium
— → 9.8
none → critical
9.8 → 5.3
critical → medium
5.3 → 9.8
medium → critical
9.8 → 5.3
critical → medium
Last analysed / modified upstream
5.3 → 7
medium → high
A flaw was found in the Linux kernel's Network File System Daemon (nfsd) for NFSv4 layouts. A race condition allows a remote attacker to trigger a kernel panic, leading to a Denial of Service (DoS). This occurs when the nfsd4_alloc_layout_stateid function accesses a file pointer without proper locking during a concurrent delegation revoke, which can be orchestrated by two NFS clients interacting with the same file.
kernel: nfsd: fix BUG_ON in nfsd4_alloc_layout_stateid on racing delegation revoke — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.
Affected:
No fix planned:
Not affected:
Affected
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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CVE-2026-89696Medium· 5.5kernel: nfsd: block non-SAVEFH ops after FOREIGN PUTFH to prevent NULL deref (CVE-2026-89696)
CVE-2026-80963Medium· 5.5kernel: dm-stats: fix a crash if allocation of per-cpu data fails (CVE-2026-80963)
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CVE-2026-89457Medium· 5.5kernel: s390/dasd: Guard sysfs discipline callbacks against unallocated private data (CVE-2026-89457)