CVE-2026-112323

Description

The AUTH_GSSAPI handler in lib/rpc/svc_auth_gssapi.c in MIT Kerberos 5 (aka krb5) 1.5.2 and later allows remote attackers to cause a denial of service (memory exhaustion in kadmind) by sending repeated failed AUTH_GSSAPI_INIT requests. Each failed request allocates client state that is only freed after a 15-minute expiration timeout, allowing an attacker to accumulate memory faster than it is reclaimed.

Statement

This vulnerability is rated as Important because an unauthenticated remote attacker can cause sustained memory exhaustion leading to a denial of service on reachable administrative endpoints without requiring valid credentials. It does not qualify for a Critical rating because the flaw does not facilitate arbitrary code execution or compromise data integrity and confidentiality. On standard Red Hat Enterprise Linux installations, the affected kadmind service is not enabled by default and is typically confined to dedicated Kerberos Key Distribution Center (KDC) environments.

Mitigation

Restrict network access to kadmind to trusted hosts, or disable it in favor of kadmin.local server-side command line tool for administration operations if possible.

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).

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

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.5N/AN/A
Attack VectorNetworkN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredNoneN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactHighN/AN/A

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (Other); DoS: Resource Consumption (Memory); DoS: Resource Consumption (CPU)

An attacker that can influence the allocation of resources that are not properly released could deplete the available resource pool and prevent all other processes from accessing the same type of resource. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.

Acknowledgements

This issue was discovered by Found by AISLE in partnership with Red Hat.

Frequently Asked Questions

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