Skip to main content
No exploitation reportedFix available

CVE-2021-42076

No exploitation reported by the sources we read.

  • Published2021-11-08
  • Fixed in2.3.4
  • WeaknessCWE-787

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 attacker can cause memory exhaustion in the barriers component (aka the server-side implementation of Barrier) and barrierc by sending long TCP messages.

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-2021-42076 Red Hat Product Security

    barrier: memory exhaustion in the server-side implementation and barrierc by sending long TCP messages

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-g73p-h925-4x6w

Frequently asked questions

What is CVE-2021-42076?

An issue was discovered in Barrier before 2.3.4. An attacker can cause memory exhaustion in the barriers component (aka the server-side implementation of Barrier) and barrierc by sending long TCP messages.

Is CVE-2021-42076 actively exploited?

Active exploitation of CVE-2021-42076 has not been confirmed. Its EPSS score was 1.6% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-42076?

CVE-2021-42076 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.

Running barrier? Hear about its next vulnerability

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record