CVE-2021-3996

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.

CVSS v3.0 5.5 MEDIUM

5.5^/10

CVSS v3.0 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb	Patch Third Party Advisory
https://access.redhat.com/security/cve/CVE-2021-3996	Issue Tracking Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2024628	Issue Tracking Patch Third Party Advisory
https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes	Release Notes Vendor Advisory
https://www.openwall.com/lists/oss-security/2022/01/24/2	Exploit Mailing List Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2022/11/30/2	Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2022/Dec/4	Mailing List Third Party Advisory
http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html	Third Party Advisory
https://security.netapp.com/advisory/ntap-20221209-0002/	Broken Link Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*

Information

Published : 2022-08-23 13:15

Updated : 2023-01-26 12:38

NVD link : CVE-2021-3996

Mitre link : CVE-2021-3996

JSON object : View

CWE

CWE-552

Files or Directories Accessible to External Parties

Products Affected

kernel

util-linux

fedoraproject

fedora

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5.5 /10