CVE-2021-3996

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.64% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 50.4% of scored records. A rank, not a probability.

NVD base score

5.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2022-08-23 00:00Z4 YR AGO

Last updated

2024-10-15 15:26Z2 YR AGO

Reserved

2021-11-22

Assigning CNA

redhat

Record state

PUBLISHED

Severity

Medium (CVSS 5.5)

CNA CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weaknesses

• CWE-552Files or Directories Accessible to External PartiesBase

Data version

5.1

Document digest

542c57d1a707eddbba0ff19e3b2a5e79df8800dc73162caa087840ee8a599f37

• mirrors.edge.kernel.orghttps://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
• github.comhttps://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb
• www.openwall.comhttps://www.openwall.com/lists/oss-security/2022/01/24/2
• bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2024628
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2021-3996
• www.openwall.com[oss-security] 20221130 Race condition in snap-confine's must_mkdir_and_open_with_perms() (CVE-2022-3328)http://www.openwall.com/lists/oss-security/2022/11/30/2mailing-list
• seclists.org20221208 Race condition in snap-confine's must_mkdir_and_open_with_perms() (CVE-2022-3328)http://seclists.org/fulldisclosure/2022/Dec/4mailing-list
• packetstormsecurity.comhttp://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20221209-0002/
• security.gentoo.orgGLSA-202401-08https://security.gentoo.org/glsa/202401-08vendor-advisory