Paper/Archive/CVE-2021-43523

CVE-2021-43523

mitre — In uClibc and uClibc-ng before 1.0.39, incorrect handling of special characters in domain names returned by DNS servers via gethostbyname…

EPSS 3%public exploit CVSS 9.6

critical.is priorityof 100

CVSS 9.6 (ADP, NVD agree)9.6 / 10 × 3028.8 Not in CISA KEV+300.0 EPSS percentile 87.7.877 × 2017.5 Exploit: SSVC poc+1010.0 SSVC exploitation: poc+100.0

Description · from the CVE record

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

ProductAffectedFixed inSource

n/an/a–CNA

Scores by source

CISA ADP9.6CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

NVD9.6CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: total

References

refuclibc-ng.org refgithub.com/wbx-github/uclibc-ng/commit/0f822af0445e5348ce7b7bd8ce1204244f31d174 refopenwall.com/lists/oss-security/2021/11/09/1