util-linux FUSE Filesystem file access

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in util-linux. Affected by this issue is some unknown functionality of the component FUSE Filesystem Handler. Such manipulation leads to file access. This vulnerability is uniquely identified as CVE-2021-3996. The attack can be launched remotely. No exploit exists. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in util-linux (version unknown) and classified as problematic. Affected by this issue is an unknown function of the component FUSE Filesystem Handler. The manipulation with an unknown input leads to a file access vulnerability. Using CWE to declare the problem leads to CWE-552. The product makes files or directories accessible to unauthorized actors, even though they should not be. Impacted is integrity, and availability. CVE summarizes:

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.

The weakness was disclosed 08/24/2022 as 166e87368ae88bf31112a30e078cceae637f4cdb. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2021-3996 since 11/22/2021. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1083.

Applying the patch 166e87368ae88bf31112a30e078cceae637f4cdb is able to eliminate this problem. The bugfix is ready for download at github.com.

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Productinfo

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 5.5
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: File access
CWE: CWE-552 / CWE-425
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: 166e87368ae88bf31112a30e078cceae637f4cdb

Timelineinfo

11/22/2021 🔍
08/24/2022 +274 days 🔍
08/24/2022 +0 days 🔍
10/16/2024 +784 days 🔍

Sourcesinfo

Product: github.com

Advisory: 166e87368ae88bf31112a30e078cceae637f4cdb
Status: Confirmed

CVE: CVE-2021-3996 (🔍)
GCVE (CVE): GCVE-0-2021-3996
GCVE (VulDB): GCVE-100-207032

Entryinfo

Created: 08/24/2022 07:53
Updated: 10/16/2024 02:13
Changes: 08/24/2022 07:53 (40), 09/25/2022 08:15 (10), 10/16/2024 02:13 (26)
Complete: 🔍
Cache ID: 216::103

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