CVE-2021-42075

Name: CVE-2021-42075
Creator: NVD / NIST
Published: 2021-11-08T04:15:08.59+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 2.13%

Last modified Jun 17, 2026

CVE-2021-42075 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An issue was discovered in Barrier before 2.3.4. The barriers component (aka the server-side implementation of Barrier) does not correctly close file descriptors for established TCP connections. EPSS estimates a 2.13% chance of exploitation in the next 30 days.

Description

An issue was discovered in Barrier before 2.3.4. The barriers component (aka the server-side implementation of Barrier) does not correctly close file descriptors for established TCP connections. An unauthenticated remote attacker can thus cause file descriptor exhaustion in the server process, leading to denial of service.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

2.13%

79.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-772

Affected Software

Vendor	Product	Versions
Barrier Project	Barrier	< 2.3.4

References

http://www.openwall.com/lists/oss-security/2021/11/02/4Exploit, Mailing List, Third Party Advisory
https://github.com/debauchee/barrier/releases/tag/v2.3.4Release Notes, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/11/02/4Exploit, Mailing List, Third Party Advisory
https://github.com/debauchee/barrier/releases/tag/v2.3.4Release Notes, Third Party Advisory

Timeline

Published: Nov 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-42075?

How severe is CVE-2021-42075?

CVE-2021-42075 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.13% probability of exploitation in the next 30 days.

How do I fix CVE-2021-42075?

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-2021-42075?

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

Scan your code now

Source: NVD / NIST