NFS: Pin the 'struct nfs_server' during a FREE_STATEID call

Summary

In the Linux kernel, the following vulnerability has been resolved: NFS: Pin the 'struct nfs_server' during a FREE_STATEID call Dan Aloni reports that he was able to hit a use-after-free bug if a FREE_STATEID operation gets delayed for whatever reason. Fix this by bumping the refcount of the 'struct nfs_server' object for the duration of the FREE_STATEID so it doesn't get cleaned up from underneath us while operations are still in flight.

Timeline

1. Aug 22, 2026, 3:33 PM UTCCVE published
2. Oct 16, 2026, 7:15 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Oct 16, 2026, 7:16 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in ed2f92ce2fc48463c41e0e540b9a3454889e8af8; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in d858ab09e787106432d4d9830bad9dfedf02f890; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in af62f1af182d33a0de38308c012841885d8ab92e; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in caee6a68ffaa5016dfc01cd0b3dc1896a32e3abd; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in ed1161ab6239761958b38d5667225634fc2be894; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in d71dfffa512e71b166a889484e4c3b148a9a3af2; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in 80ed3d762628b36c9e4b22fac7c65b72ef3b13dd; From 7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009 · fixed in cf616096a0f3a2b60f7d68b6b39674a6867ded9c

• Linux Linux

  3.10

• KernelLinux

  From 3.10.0 · fixed in 5.10.265; From 5.11.0 · fixed in 5.15.216; From 5.16.0 · fixed in 6.1.183; From 6.2.0 · fixed in 6.6.152; From 6.7.0 · fixed in 6.12.104; From 6.13.0 · fixed in 6.18.45; From 6.19.0 · fixed in 7.1.9

References 8