A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows a local user on a vulnerable system to unmount other users filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.
The product makes files or directories accessible to unauthorized actors, even though they should not be.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Util-linux | Kernel | 2.34 (including) | 2.37.3 (excluding) |
| Util-linux | Ubuntu | devel | * |
| Util-linux | Ubuntu | focal | * |
| Util-linux | Ubuntu | impish | * |
| Util-linux | Ubuntu | jammy | * |
| Util-linux | Ubuntu | upstream | * |
Web servers, FTP servers, and similar servers may store a set of files underneath a “root” directory that is accessible to the server’s users. Applications may store sensitive files underneath this root without also using access control to limit which users may request those files, if any. Alternately, an application might package multiple files or directories into an archive file (e.g., ZIP or tar), but the application might not exclude sensitive files that are underneath those directories. In cloud technologies and containers, this weakness might present itself in the form of misconfigured storage accounts that can be read or written by a public or anonymous user.