CVE-2021-3996
util-linux
MEDIUM 5.5
At a glance
- Source
- NVD
- EPSS
- EPSS 0.64 % · percentile 51 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Modified
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.
Weaknesses (CWE)
- CWE-552 — Files or Directories Accessible to External Parties
References
- https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
- https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb
- https://www.openwall.com/lists/oss-security/2022/01/24/2
- https://bugzilla.redhat.com/show_bug.cgi?id=2024628
- https://access.redhat.com/security/cve/CVE-2021-3996
- http://www.openwall.com/lists/oss-security/2022/11/30/2
- http://seclists.org/fulldisclosure/2022/Dec/4
- http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
- https://security.netapp.com/advisory/ntap-20221209-0002/
- https://security.gentoo.org/glsa/202401-08
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | CISA-ADP |
| CVSS 3.1 | MEDIUM 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
| CVSS 3.1 | MEDIUM 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
European references
- ENISA EUVD · EUVD-2021-27186
- GCVE · GCVE-0-2021-3996
CERT-FR advisories
- CERTFR-2026-AVI-0199 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1057 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0969 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0622 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:*≥ 2.34 < 2.37.3cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| util-linux | affected Fixed in util-linux v2.37.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |