Riskcovery

CVE-2026-4438

gethostbyaddr and gethostbyaddr_r return invalid DNS hostnames

State
Published
Severity
5.4 Medium
Published
Mar 20, 2026
Updated
Oct 15, 2026
Reserved
Mar 19, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.15.4 MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NCISA-ADP

Weaknesses

  • CWE-20 Improper input validation
  • CWE-88 Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

Affected Products

ProductVersions
glibcThe GNU C Library
  • 2.34 through 2.43Affected

References

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