CVE-2026-74522: Linux

High severity, CVSS 8.8. EPSS: 0.6% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in __close_file_table_ids() A ksmbd_file can remain alive after logical close while another session holds a temporary reference obtained through ksmbd_lookup_fd_inode(). ksmbd_close_fd() currently marks the file closed and drops the idr-owned reference, but leaves the pointer published in the closing session's idr until the final reference is dropped. If the foreign holder performs the final ksmbd_fd_put(), __put_fd_final() supplies the foreign session's file table to __ksmbd_close_fd(). The object is then freed without being removed from its owner's idr, and the owner session later dereferences the stale pointer during file-table teardown. Remove the volatile id from the owner's idr while ksmbd_close_fd() still holds that table's lock, and clear volatile_id before dropping the idr-owned reference. A later foreign final put then only performs physical destruction and cannot remove the object from the wrong table.

Affected products

  • Linux Linux: from 5.15.38, before 5.16 (fixed in 5.16); from 5.17.6, before 5.18 (fixed in 5.18); from 5.18, before 6.1.183 (fixed in 6.1.183); from 6.2, before 6.6.151 (fixed in 6.6.151); from 6.7, before 6.12.103 (fixed in 6.12.103); from 6.13, before 6.18.44 (fixed in 6.18.44); …

Published 2026-08-15. Last modified 2026-08-19.