CVE-2021-43566

Name: CVE-2021-43566
Creator: NVD / NIST
Published: 2022-01-11T16:15:07.813+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

LOWCVSS 2.5/10EPSS 0.38%

Last modified Jun 17, 2026

CVE-2021-43566 is a low-severity vulnerability rated 2.5/10 on the CVSS scale. All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.. EPSS estimates a 0.38% chance of exploitation in the next 30 days.

Description

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

Metrics

CVSS 3.1

2.5/10

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

EPSS Probability

0.38%

29.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-362

Affected Software

Vendor	Product	Versions
Samba	Samba	< 4.13.16

References

https://bugzilla.samba.org/show_bug.cgi?id=13979Exploit, Issue Tracking, Vendor Advisory
https://security.netapp.com/advisory/ntap-20220110-0001/Third Party Advisory
https://www.samba.org/samba/security/CVE-2021-43566.htmlPatch, Vendor Advisory
https://bugzilla.samba.org/show_bug.cgi?id=13979Exploit, Issue Tracking, Vendor Advisory
https://security.netapp.com/advisory/ntap-20220110-0001/Third Party Advisory
https://www.samba.org/samba/security/CVE-2021-43566.htmlPatch, Vendor Advisory

Timeline

Published: Jan 11, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43566?

How severe is CVE-2021-43566?

CVE-2021-43566 has a CVSS score of 2.5/10 (LOW severity). The EPSS model estimates a 0.38% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43566?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-43566?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST