CVE-2026-4438
Last modified
CVE-2026-4438 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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.. EPSS estimates a 0.19% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Gnu | Glibc | >= 2.34, <= 2.43 |
References
- https://sourceware.org/bugzilla/show_bug.cgi?id=34015Exploit, Issue Tracking, Patch
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2026-4438?
How severe is CVE-2026-4438?
How do I fix CVE-2026-4438?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-44374Backstage is an open framework for building developer portal…4.3
- CVE-2026-44375Nerdbank.MessagePack is a NativeAOT-compatible MessagePack s…7.5
- CVE-2026-44376CubeCart is an ecommerce software solution. Prior to 6.7.0, …6.1
- CVE-2026-44377CubeCart is an ecommerce software solution. Prior to 6.7.0, …9.1
- CVE-2026-44378Botan is a C++ cryptography library. Prior to 3.12.0, certai…7.5
- CVE-2026-44379MISP is an open source threat intelligence and sharing platf…5.3
- CVE-2026-44380MISP is an open source threat intelligence and sharing platf…7.2
- CVE-2026-44381MISP is an open source threat intelligence and sharing platf…5.3
- CVE-2026-44383Multiple connections to the backend using the same charging …8.7
- CVE-2026-44387ELECOM wireless LAN routers and access points devices contai…5.2
- CVE-2026-4439Out of bounds memory access in WebGL in Google Chrome on And…8.8
- CVE-2026-44390NLnet Labs Unbound up to and including version 1.25.0 has a …5.3
Are you affected by CVE-2026-4438?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST