CVE-2021-43523

Name of the Vulnerable Software and Affected Versions uClibc versions prior to 1.0.39 uClibc-ng versions prior to 1.0.39

Description The issue is related to insufficient input validation in the uClibc and uClibc-ng libraries, which can be exploited by a remote attacker to execute arbitrary code. The problem lies in the incorrect handling of special characters in domain names returned by DNS servers via functions such as gethostbyname, getaddrinfo, gethostbyaddr, and getnameinfo. This can lead to the output of wrong hostnames, resulting in domain hijacking, or the injection of malicious data into applications, potentially causing remote code execution, cross-site scripting (XSS), application crashes, and other issues.

Recommendations For uClibc versions prior to 1.0.39, update to version 1.0.39 or later to resolve the issue. For uClibc-ng versions prior to 1.0.39, update to version 1.0.39 or later to resolve the issue. As a temporary workaround, consider restricting the use of the gethostbyname, getaddrinfo, gethostbyaddr, and getnameinfo functions until a patch is available.