CVE-2021-3996
Publication date 1 February 2022
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
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.
Status
Package | Ubuntu Release | Status |
---|---|---|
util-linux | 22.04 LTS jammy |
Fixed 2.37.2-4ubuntu2
|
20.04 LTS focal |
Fixed 2.34-0.1ubuntu9.3
|
|
18.04 LTS bionic |
Not affected
|
|
16.04 LTS xenial |
Not affected
|
|
14.04 LTS trusty |
Not affected
|
Notes
Severity score breakdown
Parameter | Value |
---|---|
Base score | 5.5 · Medium |
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 |
References
Related Ubuntu Security Notices (USN)
- USN-5279-1
- util-linux vulnerabilities
- 9 February 2022