CVE-2021-43395

Exp

An issue was discovered in illumos before f859e7171bb5db34321e45585839c6c3200ebb90, OmniOS Community Edition r151038, OpenIndiana Hipster 2021.04, and SmartOS 20210923. A local unprivileged user can cause a deadlock and kernel panic via crafted rename and rmdir calls on tmpfs filesystems. Oracle Solaris 10 and 11 is also affected.

Published: 2022-12-26 Last update: 2025-04-14 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-43395 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-43395

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-43395

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-22 0.07% 0.03% -0.04%
2 2025-12-27 0.01% 0.07% +0.06%
3 2025-11-21 — 0.01% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-43395

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-43395

Affected software / configurations for CVE-2021-43395

Vendor Product Version Raw CPE
illumos illumos < 2022-01-18 cpe:2.3:o:illumos:illumos:*:*:*:*:*:*:*:*
omniosce omnios r151038 cpe:2.3:o:omniosce:omnios:r151038:*:*:*:community:*:*:*
openindiana openindiana hipster_2021.04 cpe:2.3:o:openindiana:openindiana:hipster_2021.04:*:*:*:*:*:*:*
joyent smartos 20210923 cpe:2.3:o:joyent:smartos:20210923:*:*:*:*:*:*:*
oracle solaris 10 cpe:2.3:o:oracle:solaris:10:*:*:*:*:*:*:*
oracle solaris 11 cpe:2.3:o:oracle:solaris:11:*:*:*:*:*:*:*

References for CVE-2021-43395

URL Tags
http://www.tribblix.org/relnotes.html Release Notes Third Party Advisory
https://github.com/illumos/illumos-gate/blob/069654420de4aade43c63c43cd2896e66945fc8a/usr/src/uts/common/fs/tmpfs/tmp_vnops.c Exploit Third Party Advisory
https://github.com/illumos/illumos-gate/blob/b3403853e80914bd0aade9b5b605da4878078173/usr/src/uts/common/fs/tmpfs/tmp_dir.c Exploit Third Party Advisory
https://github.com/illumos/illumos-gate/commit/f859e7171bb5db34321e45585839c6c3200ebb90 Patch Third Party Advisory
https://illumos.topicbox.com/groups/developer/T1c9e4f27f8c2f959/security-heads-up-illumos14424 Vendor Advisory
https://jgardner100.wordpress.com/2022/01/20/security-heads-up/ Third Party Advisory
https://kebe.com/blog/?p=505 Third Party Advisory
https://www.illumos.org/issues/14424 Issue Tracking Patch Vendor Advisory
https://www.oracle.com/security-alerts/cpujan2022.html Patch Third Party Advisory
cvelogic Threat Intelligence