Cross-site Scripting (XSS) Affecting c-ares package, versions <1.17.1-1.1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
2.81% (86th percentile)

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  • Snyk IDSNYK-ECHOLATEST-CARES-19643589
  • published8 Sept 2026
  • disclosed23 Nov 2021

Introduced: 23 Nov 2021

CVE-2021-3672  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Echo:latest c-ares to version 1.17.1-1.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream c-ares package and not the c-ares package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.

CVSS Base Scores

version 3.1