Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessObtain or compromise 'view-clients' admin credential
-
DeliveryAuthenticate to Keycloak Admin REST API over network
-
ExploitInvoke evaluate-scopes endpoint with arbitrary userId values
-
ExecutionEnumerate realm user identities, claims, and authorization grants
-
ImpactExfiltrate PII for realm users
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Object-level authorization, IDOR prevention
|
| Exploitation Conditions | Exploitation requires an authenticated session to the Keycloak Admin REST API using credentials that hold at minimum the 'view-clients' role within the target realm; this is confirmed by the CVSS PR:H (High Privileges Required) designation. The 'evaluate-scopes' Admin API endpoint must be reachable over the network - if the Admin API is firewalled to trusted hosts only, remote exploitation is blocked. Exploitation does NOT require a realm administrator role or higher-privileged assignments. The vulnerability is NOT exploitable by unauthenticated users or by regular (non-admin) Keycloak end-users. Exploitation is limited to the confidentiality plane (no write access, no service disruption) and is scoped to the realm(s) the compromised admin account has access to. There is no dependency on a specific Keycloak configuration toggle or non-default feature - any deployment where 'view-clients' role assignments exist and the Admin API is network-accessible meets the exploitation conditions. |
| Impact | The CVSS base score of 4.9 (Medium) reflects a tension between the high confidentiality impact (C:H) and the high privilege prerequisite (PR:H). In practice, exploitation requires a valid Keycloak admin credential with the 'view-clients' role, which substantially limits the exposed population to insider threats, account compromise scenarios, or over-provisioned service accounts. The unchanged scope (S:U) confirms that the attacker cannot pivot to broader system compromise through this vulnerability alone. No EPSS score was provided in the source data, so probabilistic exploitation likelihood cannot be quantified. The vulnerability is not listed in the CISA KEV catalog and no public proof-of-concept code has been identified, both of which reduce urgency for organizations without high-privilege account exposure. However, the PII leakage consequence is material for GDPR and compliance-sensitive deployments - the ability to enumerate realm-wide user identities and their authorization grants using a low-privilege role is a meaningful privilege escalation of information access. The attack complexity is low (AC:L), meaning once the prerequisite credential is obtained, exploitation requires no special knowledge or timing. Organizations with many delegated admins or externally accessible Admin API endpoints should treat this as a higher operational priority than the raw CVSS score implies. |
| Exploit ScenarioDerived | An insider threat actor - or an attacker who has compromised a service account or low-privilege admin credential - authenticates to Keycloak's Admin API using credentials that carry the 'view-clients' role. The attacker then iterates the evaluate-scopes endpoint with sequentially or randomly chosen userId values, harvesting user identities, email addresses, claims, and authorization grants for users across the entire realm without any additional escalation. No public proof-of-concept code has been identified at time of analysis, but the attack path requires only standard HTTP API calls and knowledge of the endpoint. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – May 19, 2026
Unauthorized PII disclosure in Red Hat Build of Keycloak allows a low-privilege administrator holding only the 'view-clients' role to enumerate user identities and authorization grants across the entire realm by invoking the 'evaluate-scopes' Admin API endpoint with an arbitrary userId parameter. The vulnerability is an Insecure Direct Object Reference (CWE-639) in the Admin API layer, exploitable remotely over the network without requiring additional user interaction. No active exploitation has been confirmed (not in CISA KEV) and no public exploit code has been identified at time of analysis, though the low attack complexity and clear abuse path make targeted insider or compromised-credential scenarios a realistic concern.
RemediationAI
No specific patched version number is confirmed in the available data; affected version boundaries and the fix release should be verified directly via the Red Hat security advisory at https://access.redhat.com/security/cve/CVE-2026-37978. Until a patch is applied, organizations should take the following specific compensating actions: audit and revoke unnecessary assignments of the 'view-clients' role across all realms, restricting it to accounts where it is operationally required; restrict network access to Keycloak's Admin API (typically /auth/admin/* or /admin/*) to trusted internal networks or management VLANs, blocking exposure from internet-facing or broadly accessible network segments; enable Keycloak's Admin API event logging to detect anomalous evaluate-scopes calls with varying userId parameters as an indicator of abuse; and review service accounts and CI/CD credentials that may hold the 'view-clients' role to ensure they are not over-provisioned. Note that restricting Admin API network access may impact legitimate administrative tooling and should be tested in non-production environments first.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in maven
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Keycloak's Admin REST API exposes an 'evaluate-scopes' endpoint designed to allow administrators to inspect the effective OAuth/OIDC scopes and claims for a given user-client pairing. The underlying flaw (CWE-639: Authorization Bypass Through User-Controlled Key) occurs because the API accepts a caller-supplied userId parameter without enforcing that the invoking principal's role permissions are scoped to that specific user or are sufficient to view cross-user identity data. A 'view-clients' role is a read-only, limited administrative role in Keycloak's fine-grained Admin permissions model - it is not intended to grant visibility into arbitrary users' identity attributes or authorization state. The CPE string cpe:2.3:a:red_hat:red_hat_build_of_keycloak:*:*:*:*:*:*:*:* indicates the wildcard version range affects all tracked releases of the Red Hat Build of Keycloak product line. The CVSS vector AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N confirms the vulnerability is network-reachable, requires no interaction, and produces high confidentiality impact with no integrity or availability consequences.
Know when Red Hat Build Of Keycloak gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
DescriptionCVE.org
A flaw was found in Keycloak. A low-privilege administrator with the 'view-clients' role can exploit this by invoking the 'evaluate-scopes' Admin API endpoints with an arbitrary user ID (userId) parameter. This vulnerability allows for cross-role personally identifiable information (PII) leakage, enabling unauthorized visibility into user identities and authorizations across the realm. Exploitation is possible remotely via network access to the Admin API.
Blast Radius
ecosystem impact- 61 maven packages depend on org.keycloak:keycloak-services (28 direct, 33 indirect)
Ecosystem-wide dependent count for version 26.6.2.
Threat Intelligence Overview
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.
Affected Products (CPE)CVE.org
More in Red Hat Build Of Keycloak
View allAccount takeover in Red Hat Build of Keycloak allows an unauthenticated attacker to abuse the reset-credentials flow in
Account takeover in Keycloak (Red Hat build of Keycloak, Red Hat Single Sign-On 7) arises because the IdP-initiated SAML
Authentication bypass in Red Hat Build of Keycloak (and Red Hat Single Sign-On 7) lets an unauthenticated attacker forge
Privilege escalation in Red Hat Build of Keycloak's Dynamic Client Registration (DCR) grants an attacker with low-privil
Mismatched handling of the HTTP/1 absolute-form request authority in Red Hat build of Quarkus and other affected Red Hat
Authorization bypass in the Keycloak Policy Enforcer allows any authenticated user to circumvent all enforced access con
URI normalization bypass in Keycloak's Authorization Services PathMatcher allows authenticated low-privilege users to re
Privilege escalation in Keycloak's Dynamic Client Registration (DCR) component allows attackers with standard user accou
Token exchange in Keycloak bypasses Google Workspace domain allowlist restrictions, enabling any valid Google account ho
Signature-verification bypass in Keycloak (and Red Hat's Keycloak-based products such as Red Hat Single Sign-On 7 and Re
Tenant-restriction bypass in Keycloak's Microsoft identity provider integration allows attackers holding any valid Micro
Session hijacking via SAML assertion replay in Keycloak's SAML broker component allows adjacent-network attackers to aut
EUVD-2026-30882
GHSA-rrv7-3mqf-hxfr
NVD
CVE.org
EPSS
Vulnrichment
VulDB
Exploit-DB