EUVD-2026-12690
GHSA-x4p7-7chp-64hq
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessCraft valid SAML response from external IdP
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DeliverySend to Keycloak SAML endpoint
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ExploitBypass disabled IdP checks
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ExecutionComplete broker login authentication
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ImpactGain unauthorized access to account
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A07:2025 - Authentication Failures
ASVS 5.0
V6 - Authentication Authentication required for critical functions
MITRE ATT&CK
1 technique across 1 tactic: Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Keycloak must have SAML IdP-initiated broker login enabled. Attacker requires valid SAML response from external IdP. Requires low-privilege authenticated access to Keycloak. No victim interaction needed. |
| Impact | The real-world risk is elevated due to the network-based attack vector (AV:N) and low attack complexity (AC:L), requiring only low privileges (PR:L) and no user interaction (UI:N). The CVSS 8.1 score appropriately reflects high impact to confidentiality and integrity, though availability remains unaffected. While no EPSS score or KEV listing is provided in the data, the vulnerability's technical characteristics suggest moderate exploitation likelihood in environments where disabled SAML IdPs are expected to be fully inactive. The attack requires prior knowledge of valid SAML response formats and an authenticated attacker with low-level access, which somewhat limits the attack surface compared to completely unauthenticated vulnerabilities. Organizations using SAML federation with multiple IdPs where some are temporarily or permanently disabled face the highest risk, as this represents a security control bypass that administrators may rely upon for access restriction. The availability of patches from Red Hat (RHSA-2026:3925, RHSA-2026:3926, RHSA-2026:3947, RHSA-2026:3948) and the specificity of affected versions indicate this is a confirmed, actionable vulnerability requiring prompt remediation rather than theoretical risk. |
| Exploit ScenarioDerived | An attacker with low-level authenticated access to the network obtains a valid SAML response format from a previously-used or externally-controlled Identity Provider that has been administratively disabled in Keycloak. The attacker crafts and sends this SAML response directly to the Keycloak SAML broker endpoint for IdP-initiated logins, bypassing the disabled state check and successfully authenticating as a user from that IdP. This grants the attacker unauthorized access to applications and resources protected by Keycloak, effectively circumventing administrative security controls intended to revoke access from specific identity sources. |
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Alert meAnalysisAIv1 – Mar 18, 2026
Keycloak contains an authentication bypass vulnerability in its SAML broker functionality that allows remote attackers with low-level privileges to complete IdP-initiated broker logins even when the SAML Identity Provider has been administratively disabled. Red Hat Build of Keycloak versions 26.2 and 26.4 are affected, with patches available in versions 26.2-16, 26.2.14-1, 26.4-12, and 26.4.10-1. The CVSS score of 8.1 reflects high confidentiality and integrity impact, though no evidence of active exploitation (KEV) or public proof-of-concept has been reported at this time.
RemediationAI
Immediately upgrade to patched versions of Red Hat Build of Keycloak: version 26.2-16 or 26.2.14-1 for the 26.2 series, or version 26.4-12 or 26.4.10-1 for the 26.4 series, as detailed in Red Hat security advisories RHSA-2026:3925, RHSA-2026:3926, RHSA-2026:3947, and RHSA-2026:3948 (see https://access.redhat.com/errata/). Until patching is completed, implement network-level access controls to restrict the Keycloak SAML endpoint to trusted IP ranges only, audit all SAML IdP configurations to verify enabled/disabled states match security policies, and monitor authentication logs for unexpected IdP-initiated logins from disabled providers. As an additional interim control, consider removing or invalidating SAML metadata for disabled IdPs from the Keycloak configuration to prevent acceptance of assertions from those sources. Review all recent authentication events to identify potential exploitation attempts where disabled IdPs successfully authenticated users.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in maven
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability affects the SAML (Security Assertion Markup Language) broker implementation in Keycloak, Red Hat's open-source identity and access management solution. The flaw stems from CWE-306 (Missing Authentication for Critical Function), where the SAML endpoint processing IdP-initiated broker logins fails to properly validate whether the configured Identity Provider is enabled before accepting authentication assertions. Affected products include Red Hat Build of Keycloak 26.2 (CPE: cpe:2.3:a:red_hat:red_hat_build_of_keycloak_26.2) and 26.4 (CPE: cpe:2.3:a:red_hat:red_hat_build_of_keycloak_26.4). The vulnerability exists in the broker login flow where external IdPs send SAML responses to Keycloak's SAML endpoint, and the system processes these responses without checking the administrative state of the IdP configuration.
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
Lifecycle Timeline
2DescriptionCVE.org
A flaw was found in Keycloak. A remote attacker could bypass security controls by sending a valid SAML response from an external Identity Provider (IdP) to the Keycloak SAML endpoint for IdP-initiated broker logins. This allows the attacker to complete broker logins even when the SAML Identity Provider is disabled, leading to unauthorized authentication.
Blast Radius
ecosystem impact- 53 maven packages depend on org.keycloak:keycloak-server-spi-private (22 direct, 31 indirect)
- 43 maven packages depend on org.keycloak:keycloak-services (15 direct, 28 indirect)
Ecosystem-wide dependent count for version 26.5.5 and other introduced versions.
Executive ViewAI
Keycloak's SAML authentication endpoint contains a critical flaw that allows attackers to bypass identity provider controls and gain unauthorized access to systems, even when those providers are disabled. Organizations relying on Keycloak for federated identity management face immediate risk of unauthorized user authentication and potential lateral movement into protected resources.
Disable SAML IdP-initiated broker login feature if operationally feasible; implement Web Application Firewall (WAF) rules to validate SAML response signatures and reject responses from disabled IdPs; restrict network access to Keycloak SAML endpoints via firewall segmentation; enforce strict rate limiting on authentication endpoints; implement enhanced logging and alerting for SAML authentication failures; conduct manual validation of external IdP provider status before accepting SAML responses at application layer if possible.
Threat Intelligence Overview
NVD
CVE.org
EPSS
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
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Unauthenticated remote attackers can exhaust memory in Red Hat Build of Keycloak 26.4 and 26.4.10 by sending highly comp
Account lockout in the Red Hat build of Keycloak 26.4 and 26.6 lets an unauthenticated remote attacker deny access to a
Same technique Authentication Bypass
View allVendor StatusVendor
Debian
Bug #1088287| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| open | - | - |
Exploit-DB