Vulnerability identifier: #VU60005

Vulnerability risk: Low

CVSSv3.1: 2.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-3996

CWE-ID: CWE-264

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Util-linux
Universal components / Libraries / Libraries used by multiple products

Vendor: kernel.org

Description

The vulnerability allows a local user to bypass implemented security restrictions.

The vulnerability exists due to improper UID check in libmount. A local user can unmount FUSE filesystems of users with similar UID.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Util-linux: 2.2 - 2.37.2

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External links
http://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
http://www.openwall.com/lists/oss-security/2022/01/24/2

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.