CVE-2026-4438 (GCVE-0-2026-4438)

Vulnerability from cvelistv5 – Published: 2026-03-20 19:59 – Updated: 2026-07-14 12:45
VLAI
Title
gethostbyaddr and gethostbyaddr_r return invalid DNS hostnames
Summary
Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C library version 2.34 to version 2.43 could result in an invalid DNS hostname being returned to the caller in violation of the DNS specification.
Severity
5.4 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 15:06 UTC
CWE
  • CWE-20 - Improper input validation
  • CWE-88 - Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
Assigner
References
Impacted products
Date Public
2026-03-20 22:17
Credits
Antonio Maini (0rbitingZer0) - 0rbitingZer0@proton.me
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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