Medium
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-3996
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:41 UTC · Revision 1
Source evidence
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.
osv:CVE-2021-3996
Complete source record
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