CVE-2026-4438

CVE Details

Release Date:	2026-03-20
Impact:	Low	What is this?

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.

See more information about CVE-2026-4438 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	4.0
Vector String:	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Version:	3.1
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	None
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	Low
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (glibc)	ELSA-2026-20597	2026-06-23