cbcvebase.
CVE-2026-4437
published 2026-03-20

CVE-2026-4437: 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…

high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
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.

Affected

6 ranges
VendorProductVersion rangeFixed in
debianglibc< glibc 2.42-14 (forky)glibc 2.42-14 (forky)
gnuglibc>= 0 < 2.42-142.42-14
gnuglibc2.34 – 2.43
msrcazl3_glibc_2.38-18_on_azure_linux_3.0
msrccbl2_glibc_2.35-10_on_cbl_mariner_2.0
the_gnu_c_libraryglibc2.34 – 2.43

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH