CVE-2021-3996

mediumpriority · track · 22EPSS 0.006 · 51 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.64% (51st) EPSS
CVSS 5.5 · medium
Is it mine?
11 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

5.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.3–5.5

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 3.6
v3.13.3lowAV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 1.8 · impact 3.6
v3.15.1mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-264USCWE-552US
04

affected products (11)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2022-0279util-linux: Mehrere Schwachstellen ermöglichen Umgehen von SicherheitsvorkehrungenDeutsch2022-01-24csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen in util-linux ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundnvdNVDCVE.orgMITRE
published 2022-08-23modified 2026-06-17
08

references (39)

External citations — patches, advisories, analysis.

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