CVE-2026-46040: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(), the error path calls inotify_remove_from_idr() but does not call dec_inotify_watches() to undo the preceding inc_inotify_watches(). This leaks a watch count, and repeated failures can exhaust the max_user_watches limit with -ENOSPC even when no watches are active. Prior to commit 1cce1eea0aff ("inotify: Convert to using per-namespace limits"), the watch count was incremented after fsnotify_add_mark_locked() succeeded, so this path was not affected. The conversion moved inc_inotify_watches() before the mark insertion without adding the corresponding rollback. Add the missing dec_inotify_watches() call in the error path.

Affected products

  • Linux Linux Kernel: from 4.11, before 5.10.258 (fixed in 5.10.258); from 5.11, before 5.15.209 (fixed in 5.15.209); from 5.16, before 6.1.175 (fixed in 6.1.175); from 6.2, before 6.6.140 (fixed in 6.6.140); from 6.7, before 6.12.86 (fixed in 6.12.86); from 6.13, before 6.18.27 (fixed in 6.18.27); …

Published 2026-05-27. Last modified 2026-09-08.