Vulnerability 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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Uclibc | Uclibc | <= 0.9.33.2 |
| Uclibc-Ng Project | Uclibc-Ng | < 1.0.39 |
Related Weaknesses (CWE)
References
- https://github.com/wbx-github/uclibc-ng/commit/0f822af0445e5348ce7b7bd8ce1204244PatchThird Party Advisory
- https://uclibc-ng.org/Vendor Advisory
- https://www.openwall.com/lists/oss-security/2021/11/09/1ExploitMailing ListThird Party Advisory
- https://github.com/wbx-github/uclibc-ng/commit/0f822af0445e5348ce7b7bd8ce1204244PatchThird Party Advisory
- https://uclibc-ng.org/Vendor Advisory
- https://www.openwall.com/lists/oss-security/2021/11/09/1ExploitMailing ListThird Party Advisory
FAQ
What is CVE-2021-43523?
CVE-2021-43523 is a vulnerability with a CVSS score of 9.6 (CRITICAL). 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 outpu...
How severe is CVE-2021-43523?
CVE-2021-43523 has been rated CRITICAL with a CVSS base score of 9.6/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2021-43523?
Check the references section above for vendor advisories and patch information. Affected products include: Uclibc Uclibc, Uclibc-Ng Project Uclibc-Ng.