CVE-2022-49281

What it is

In the Linux kernel, the following vulnerability has been resolved: cifs: fix handlecache and multiuser In multiuser each individual user has their own tcon structure for the share and thus their own handle for a cached directory. When we umount such a share we much make sure to release the pinned down dentry for each such tcon and not just the master tcon. Otherwise we will get nasty warnings on umount that dentries are still in use: [ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/} still in use\ (2) [unmount of cifs cifs] ... [ 3459.590492] Call Trace: [ 3459.590500] d_walk+0x61/0x2a0 [ 3459.590518] ? shrink_lock_dentry.part.0+0xe0/0xe0 [ 3459.590526] shrink_dcache_for_umount+0x49/0x110 [ 3459.590535] generic_shutdown_super+0x1a/0x110 [ 3459.590542] kill_anon_super+0x14/0x30 [ 3459.590549] cifs_kill_sb+0xf5/0x104 [cifs] [ 3459.590773] deactivate_locked_super+0x36/0xa0 [ 3459.590782] cleanup_mnt+0x131/0x190 [ 3459.590789] task_work_run+0x5c/0x90 [ 3459.590798] exit_to_user_mode_loop+0x151/0x160 [ 3459.590809] exit_to_user_mode_prepare+0x83/0xd0 [ 3459.590818] syscall_exit_to_user_mode+0x12/0x30 [ 3459.590828] do_syscall_64+0x48/0x90 [ 3459.590833] entry_SYSCALL_64_after_hwframe+0x44/0xae

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2025-02-26 07:01 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 05:17 UTC Last updatedMost recent change to the record

Details

Published

2025-02-26 07:01 UTC

Last modified

2026-06-17 05:17 UTC

Exploit probability

0.3% · EPSS, next 30 days

Record status

Analyzed

Affected

• Linux Kernel < 5.15.33
• Linux Kernel < 5.16.19
• Linux Kernel < 5.17.2

Attack profile CVSS 3.1 · 5.5

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High