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No exploitation reportedFix available

CVE-2021-4124

No exploitation reported by the sources we read.

  • Published2021-12-16
  • WeaknessCWE-79

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

janus-gateway is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Timeline

dates in UTC
  1. 2021-12-1614:15CVE publishedNVD

Versions per branch

NVD
Meetecho janus
BranchAffectedFixed in
0.11≤ 0.11.6no fix published

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.

Packages

  • janusUbuntu:20.04:LTSall versions · no fixed version listed
  • janusUbuntu:18.04:LTSall versions · no fixed version listed
  • janusDebian:14all versions · no fixed version listed
  • janusDebian:12all versions · no fixed version listed

Full record on NVD

Fix

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

  • NVDCVSS 3.16.1read 2026-10-23
  • CNACVSS 3.08.1known since 2026-10-23
  • NVDCVSS 2.04.3read 2026-10-23
  • CNAweakness (CWE)CWE-79known since 2026-10-23
  • FIRST EPSSEPSS score1.0 %2026-11-08
  • OSVaffected packages—
  • GitHub Advisoriesadvisory—

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Published
2021-12-16
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-gv3q-27qx-g2xh

Frequently asked questions

What is CVE-2021-4124?

janus-gateway is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Is CVE-2021-4124 actively exploited?

Active exploitation of CVE-2021-4124 has not been confirmed. Its EPSS score was 1.0% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-4124?

CVE-2021-4124 has a CVSS v3 base score of 6.1 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

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Sources for this record