CVE 2026 110931

A flaw was found in the SAML 1.1 assertion parser of Keycloak, a tool used for identity and access management. The issue occurs when the parser handles a specific element called AuthorityBinding within an authentication statement. Due to an incomplete fix for a vulnerability, the parser can enter an infinite loop that consumes all available memory, causing the entire Keycloak service to crash and become unavailable to users.

The Red Hat Product Security team has assessed the severity of this vulnerability as Important, given that it can be exploited by a remote, unauthenticated attacker with a single request. Successful exploitation allows an attacker to cause a complete Denial of Service by terminating the JVM via memory exhaustion. The vulnerability's root cause is an infinite loop in the SAML 1.1 AuthorityBinding parsing logic, which was missed during the remediation of CVE-2026-7307.

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.

Bugzilla 2553047 : keycloak-services: keycloak-services: Unauthenticated JVM termination via SAML 1.1 AuthorityBinding parsing loop

CWE-835 : Loop with Unreachable Exit Condition

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

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

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

An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.

Red Hat would like to thank Animesh Roy for reporting this issue.

Frequently Asked Questions

"Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.

The term 'Affected' means that our Analysis team has determined that this product, such as Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to address this issue in the near future. This includes all minor releases of this product unless noted otherwise in the Statement text.

Upgrade to a supported product version that includes a fix for this vulnerability (recommended).

Apply a mitigation (if one exists).

Customers with the Technical Account Manager (TAM) RHEL Security Select Add-on can review this CVE directly with their TAM.

Apply a mitigation (if one exists).

Red Hat Engineering focuses on addressing high-priority issues based on the impact and product lifecycle expectations. Therefore, lower-priority issues will not receive immediate fixes.

Customers with the technical account manager (TAM) RHEL Security Select Add-on can review this CVE directly with their TAM.

Not sure what something means? Check out our Security Glossary .

For clarification or corrections, please Red Hat Product Security .