util-linux is a random collection of Linux utilities. In util-linux 2.39 through 2.41.4 and 2.42 through 2.42.1, the SUID mount utilitys hook_owner.c post-mount hook performs path-based chmod() and lchown() operations on a previously validated mount target. A local low-privileged user authorized by an /etc/fstab entry with user or users and an X-mount.mode, X-mount.owner, or X-mount.group option can use renameat2(RENAME_EXCHANGE) to race a writable ancestor of the target and redirect the privileged ownership or mode change to a root-owned path, potentially gaining root privileges. This issue is fixed in 2.41.5 and 2.42.2.
Weakness
The product checks the state of a resource before using that resource, but the resource’s state can change between the check and the use in a way that invalidates the results of the check.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Util-linux | Ubuntu | noble | * |
| Util-linux | Ubuntu | questing | * |
| Util-linux | Ubuntu | resolute | * |
| Util-linux | Ubuntu | stonking | * |
| Util-linux | Ubuntu | upstream | * |
Potential Mitigations
Related Attack Patterns
References
- https://github.com/util-linux/util-linux/commit/24da33905c7115c4cbccd0afb2a469804e96467a
- https://github.com/util-linux/util-linux/commit/722c96974dd4009a334e4aee556eedaab5fb94b4
- https://github.com/util-linux/util-linux/commit/897a08c2b11dfa66975c3d24d63c7bf5f5be1a7c
- https://github.com/util-linux/util-linux/commit/d0c5adaeb3a3d823aba1377794de8f009b8152cc
- https://github.com/util-linux/util-linux/releases/tag/v2.41.5
- https://github.com/util-linux/util-linux/releases/tag/v2.42.2
- https://github.com/util-linux/util-linux/security/advisories/GHSA-g8wm-75wr-g2vh
- https://github.com/util-linux/util-linux/security/advisories/GHSA-g8wm-75wr-g2vh