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No exploitation reportedFix available

CVE-2021-42074

No exploitation reported by the sources we read.

  • Published2021-11-08
  • Fixed in2.3.4
  • WeaknessCWE-416

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

An issue was discovered in Barrier before 2.3.4. An unauthenticated attacker can cause a segmentation fault in the barriers component (aka the server-side implementation of Barrier) by quickly opening and closing TCP connections while sending a Hello message for each TCP session.

Timeline

dates in UTC
  1. 2021-11-0804:15CVE publishedNVD

Versions per branch

NVD
Barrier project barrier
BranchAffectedFixed in
2.3< 2.3.42.3.4

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • CVE-2021-42074 Red Hat Product Security

    barrier: segmentation fault in the server-side implementation by quickly opening and closing TCP connections while sending a hello message

Full record on NVD

Fix

  1. Update Barrier project barrier to 2.3.4

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2021-11-08
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-97hp-rfmm-2c7w

Frequently asked questions

What is CVE-2021-42074?

An issue was discovered in Barrier before 2.3.4. An unauthenticated attacker can cause a segmentation fault in the barriers component (aka the server-side implementation of Barrier) by quickly opening and closing TCP connections while sending a Hello message for each TCP session.

Is CVE-2021-42074 actively exploited?

Active exploitation of CVE-2021-42074 has not been confirmed. Its EPSS score was 1.8% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-42074?

CVE-2021-42074 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record