CVE-2021-42072

Name: CVE-2021-42072
Creator: NVD / NIST
Published: 2021-11-08T04:15:08.437+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 1.60%

Last modified Jun 17, 2026

CVE-2021-42072 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. An issue was discovered in Barrier before 2.4.0. The barriers component (aka the server-side implementation of Barrier) does not sufficiently verify the identify of connecting clients. EPSS estimates a 1.60% chance of exploitation in the next 30 days.

Description

An issue was discovered in Barrier before 2.4.0. The barriers component (aka the server-side implementation of Barrier) does not sufficiently verify the identify of connecting clients. Clients can thus exploit weaknesses in the provided protocol to cause denial-of-service or stage further attacks that could lead to information leaks or integrity corruption.

Metrics

CVSS 3.1

8.8/10

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

EPSS Probability

1.60%

72.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-287

Affected Software

Vendor	Product	Versions
Barrier Project	Barrier	< 2.4.0
Fedoraproject	Fedora	34
Fedoraproject	Fedora	35

References

http://www.openwall.com/lists/oss-security/2021/11/02/4Exploit, Mailing List, Third Party Advisory
https://github.com/debauchee/barrier/releases/tag/v2.4.0Release Notes, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CIEVNCFEFO7L3NTM4VUZB3WKYYCBTFCI/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XMU3STOKHPEZSC54MZ42YBFFC2R3BU2Q/
http://www.openwall.com/lists/oss-security/2021/11/02/4Exploit, Mailing List, Third Party Advisory
https://github.com/debauchee/barrier/releases/tag/v2.4.0Release Notes, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CIEVNCFEFO7L3NTM4VUZB3WKYYCBTFCI/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XMU3STOKHPEZSC54MZ42YBFFC2R3BU2Q/

Timeline

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

Frequently Asked Questions

What is CVE-2021-42072?

How severe is CVE-2021-42072?

CVE-2021-42072 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 1.60% probability of exploitation in the next 30 days.

How do I fix CVE-2021-42072?

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-2021-42072?

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

Scan your code now

Source: NVD / NIST