CVE-2026-112201

Description

A flaw was found in the login-failure storage component of Keycloak, the identity and access management solution. This issue specifically affects deployments using MySQL or MariaDB databases in a multi-node configuration. When multiple failed login attempts occur simultaneously for the same account, a synchronization error can cause the system to enter a repetitive loop that locks the user's record in the database. This results in legitimate login attempts for that user being blocked and failing with an error. Furthermore, because some failures are not correctly recorded during this loop, the system's brute-force protection may not accurately count all failed attempts.

Statement

The Red Hat Product Security team has assessed the severity of this vulnerability as Moderate, given that it requires a specific race condition to be triggered on multi-node deployments using specific database backends. Successful exploitation allows an attacker to cause a localized denial of service for specific user accounts and potentially bypass brute-force protection limits. The vulnerability's root cause is an improper reliance on database-specific affected-row counts during concurrent upsert operations in the JPA models.

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).

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

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score4.8N/AN/A
Attack VectorNetworkN/AN/A
Attack ComplexityHighN/AN/A
Privileges RequiredNoneN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactLowN/AN/A
Availability ImpactLowN/AN/A

Vector

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

Understanding the Weakness (CWE)

Availability

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

When a race condition makes it possible to bypass a resource cleanup routine or trigger multiple initialization routines, it may lead to resource exhaustion.

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Instability

When a race condition allows multiple control flows to access a resource simultaneously, it might lead the product(s) into unexpected states, possibly resulting in a crash.

Confidentiality,Integrity

Technical Impact: Read Files or Directories; Read Application Data

When a race condition is combined with predictable resource names and loose permissions, it may be possible for an attacker to overwrite or access confidential data (CWE-59).

Access Control

Technical Impact: Execute Unauthorized Code or Commands; Gain Privileges or Assume Identity; Bypass Protection Mechanism

This can have security implications when the expected synchronization is in security-critical code, such as recording whether a user is authenticated or modifying important state information that should not be influenced by an outsider.

Acknowledgements

Red Hat would like to thank Semih Doğan for reporting this issue.

Frequently Asked Questions

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