CVE-2021-43395

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

0.32% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 24.1% 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

No Red Hat rating. Red Hat rates the CVEs that affect its products.

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

2022-12-26 00:00Z3 YR AGO

Last updated

2025-04-14 16:10Z1 YR AGO

Reserved

2021-11-04

Assigning CNA

mitre

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-667Improper LockingClass

Data version

5.1

Document digest

3431248cf7422ba2f24689dbdcaa0a20439a0c46d673d0abf5b0034a2a906b8a

• github.comhttps://github.com/illumos/illumos-gate/blob/069654420de4aade43c63c43cd2896e66945fc8a/usr/src/uts/common/fs/tmpfs/tmp_vnops.c
• github.comhttps://github.com/illumos/illumos-gate/blob/b3403853e80914bd0aade9b5b605da4878078173/usr/src/uts/common/fs/tmpfs/tmp_dir.c
• www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2022.html
• www.tribblix.orghttp://www.tribblix.org/relnotes.html
• jgardner100.wordpress.comhttps://jgardner100.wordpress.com/2022/01/20/security-heads-up/
• illumos.topicbox.comhttps://illumos.topicbox.com/groups/developer/T1c9e4f27f8c2f959/security-heads-up-illumos14424
• www.illumos.orghttps://www.illumos.org/issues/14424
• github.comhttps://github.com/illumos/illumos-gate/commit/f859e7171bb5db34321e45585839c6c3200ebb90
• kebe.comhttps://kebe.com/blog/?p=505