Rapid7

vulnerability

Debian: CVE-2021-43523: uclibc -- security update

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Nov 10, 2021
Added
May 15, 2025
Modified
Mar 30, 2026

Description

In uClibc and uClibc-ng before 1.0.39, incorrect handling of special characters in domain names returned by DNS servers via gethostbyname, getaddrinfo, gethostbyaddr, and getnameinfo can lead to output of wrong hostnames (leading to domain hijacking) or injection into applications (leading to remote code execution, XSS, applications crashes, etc.). In other words, a validation step, which is expected in any stub resolver, does not occur.

Solution

no-fix-debian-deb-package
Title
Rapid7 Labs

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