CVE-2026-4438

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://sourceware.org/bugzilla/show_bug.cgi?id=34015	Exploit Issue Tracking Patch
https://cert-portal.siemens.com/productcert/html/ssa-082556.html

Configurations

Configuration 1 (hide)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-20 20:16

Updated : 2026-07-14 13:18

NVD link : CVE-2026-4438

Mitre link : CVE-2026-4438

CVE.ORG link : CVE-2026-4438

JSON object : View

Products Affected

gnu

glibc

CWE

CWE-20

Improper Input Validation

CWE-88

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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