CVE-2026-4437 (GCVE-0-2026-4437)

Vulnerability from cvelistv5 – Published: 2026-03-20 19:59 – Updated: 2026-03-23 15:13
VLAI?
Title
gethostbyaddr and gethostbyaddr_r may incorrectly handle DNS response
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, with a crafted response from the configured DNS server, result in a violation of the DNS specification that causes the application to treat a non-answer section of the DNS response as a valid answer.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
The GNU C Library glibc Affected: 2.34 , ≤ 2.43 (custom)
Create a notification for this product.
Date Public ?
2026-03-20 22:20
Credits
Antonio Maini (0rbitingZer0) - 0rbitingZer0@proton.me Kevin Farrell
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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