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CVE-2021-3996

Published: Aug 23, 2022Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-552
NVD MITRE
5.5CVSSMEDIUM
EPSS Score
0.6%
Top 54.4%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:UC:NI:NA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-552

Affected Products

util-linuxkernel
Mixed
Operating Systems / linux-distro
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
РЕД ОСООО «Ред Софт»
On-premOS
Operating Systems / linux-distro
util-linuxСообщество свободного программного обеспечения
On-prem
Operating Systems / linux-distro
ОСОН ОСнова ОnyxАО «НППКТ»
On-premOS
Operating Systems / linux-distro
kerneloss-projectOperating Systems
fedoraprojectoss-projectUSOperating Systemsaka fedora project
ооо «ред софт»commercialRUOperating Systemsaka red soft
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ао «нппкт»commercialRUOperating Systems
and 1 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
packetstormsecurity.com
http://seclists.org/fulldisclosure/2022/Dec/4
seclists.org
http://www.openwall.com/lists/oss-security/2022/11/30/2
openwall.com
and 11 more references View all →

Timeline

Published
Aug 23, 2022
Last Updated
Nov 21, 2024

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