Rapid7

vulnerability

Ubuntu: (Multiple Advisories) (CVE-2021-3672): c-ares vulnerability

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Aug 10, 2021
Added
Aug 11, 2021
Modified
Apr 16, 2026

Description

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.

Solutions

ubuntu-pro-upgrade-libc-ares2ubuntu-upgrade-libc-ares2
Title
Rapid7 Labs

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