VULNERABILITY INTELLIGENCE

CVE-2021-43523

CVSS score9.6 CRITICAL
EPSS probability3.07%
CISA KEVNot currently listed
Published2021-11-10
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

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.

Weakness classification

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Primary references