CVE-2021-43523: XSS

Published Nov 10, 2021
·
Updated

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.

Affected Software

2 affected components
uClibc uClibc<=0.9.33.2
Uclibc-ng Project Uclibc-ng<1.0.39

Event History

Nov 10, 2021
CVE Published
via MITRE·02:03 PM
Data Sourced
via MITRE·02:03 PM
Description
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-43523?

CVE-2021-43523 has been classified as a medium severity vulnerability.

2

How do I fix CVE-2021-43523?

To fix CVE-2021-43523, you should upgrade uClibc and uClibc-ng to versions that are 1.0.39 or later.

3

What are the potential risks associated with CVE-2021-43523?

The risks associated with CVE-2021-43523 include domain hijacking and potential remote code execution due to incorrect handling of domain names.

4

Which software versions are affected by CVE-2021-43523?

CVE-2021-43523 affects uClibc versions up to and including 0.9.33.2 and uClibc-ng versions 1.0.39 and earlier.

5

What are the specific functions impacted by CVE-2021-43523?

CVE-2021-43523 impacts the functions gethostbyname, getaddrinfo, gethostbyaddr, and getnameinfo in uClibc and uClibc-ng.

Contact

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