CVE-2021-3996

medium

Description

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.

References

https://security.gentoo.org/glsa/202401-08

https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes

https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb

https://bugzilla.redhat.com/show_bug.cgi?id=2024628

https://access.redhat.com/security/cve/CVE-2021-3996

http://www.openwall.com/lists/oss-security/2022/11/30/2

http://seclists.org/fulldisclosure/2022/Dec/4

http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html

Details

Source: Mitre, NVD

Published: 2022-08-23

Risk Information

CVSS v2

Base Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium