CVE-2021-43523

CriticalCVSS 9.6/10Last modified Jun 17, 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.

Metrics

CVSS 3.1 9.6/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-79

Affected software

No affected versions have been published.

Timeline

Published: Nov 10, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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