CVE-2026-45915
Published: May 28, 2026Last modified: June 24, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: fat: avoid parent link count underflow in rmdir Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive i_nlink to 0, triggering the WARN_ON in drop_nlink(). Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the parent link count when it is at least 3, otherwise report a filesystem error.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.167-r0) |
| 25 LTS | linux-lts | Fixed (6.12.80-r0) | |
| Stream | linux-lts | Fixed (6.18.35-r1) |
References
- https://git.kernel.org/stable/c/17866f8a0822d414cb02e621cf003a7d04396ef8
- https://git.kernel.org/stable/c/7fe0de287e931e07cb96ecf1f449b2ebdb0e1115
- https://git.kernel.org/stable/c/8cafcb881364af5ef3a8b9fed4db254054033d8a
- https://git.kernel.org/stable/c/955c5d670b5ae07c78f4345e23a895638db96ce1
- https://git.kernel.org/stable/c/9894c79fd9466612d0514be157b5c30cd93aa645
- https://git.kernel.org/stable/c/cd569b87378b9c33ae13c23d6bb9d205d66f7c4b
- https://git.kernel.org/stable/c/d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0
- https://git.kernel.org/stable/c/d3b7ffa90f613938128432c7b2f35b7aa4bdd86b