CVE-2026-4438 (GCVE-0-2026-4438)
Vulnerability from cvelistv5 – Published: 2026-03-20 19:59 – Updated: 2026-10-15 01:12
VLAI
EPSS
VEX
Title
gethostbyaddr and gethostbyaddr_r return invalid DNS hostnames
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 result in an invalid DNS hostname being returned to the caller in violation of the DNS specification.
Severity
5.4 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 15:06 UTC
CWE
Assigner
References
Impacted products
4 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| The GNU C Library | glibc |
Affected:
2.34 , ≤ 2.43
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed | |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed |
Date Public
2026-03-20 22:17
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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