CVE-2026-4438
Description
A flaw was found in the GNU C library (glibc). When applications use the gethostbyaddr or gethostbyaddr_r functions with a nsswitch.conf configuration that specifies glibc's DNS backend, the library may return an invalid DNS hostname. This violates the DNS specification and could lead to applications receiving incorrect hostname information, potentially impacting network operations or security decisions.
Statement
This is a LOW impact flaw where glibc's gethostbyaddr and gethostbyaddr_r functions may return an invalid DNS hostname. This occurs when applications use a nsswitch.conf configuration that specifies glibc's DNS backend. This could lead to applications receiving incorrect hostname information, potentially affecting network operations or security decisions on Red Hat Enterprise Linux and OpenShift Container Platform.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4 | N/A | 5.4 |
| Attack Vector | Local | N/A | Adjacent Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
cve.org: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Application Data; Execute Unauthorized Code or Commands
An attacker could modify the structure of the message or data being sent to the downstream component, possibly injecting commands.
Frequently Asked Questions
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