EUVD-2026-18208
GHSA-hj93-h7pg-fh6v
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Lifecycle Timeline
5Blast Radius
ecosystem impact- 53 maven packages depend on org.keycloak:keycloak-services (25 direct, 28 indirect)
Ecosystem-wide dependent count for version 26.5.7.
DescriptionCVE.org
A flaw was found in Keycloak. The SingleUseObjectProvider, a global key-value store, lacks proper type and namespace isolation. This vulnerability allows an unauthenticated attacker to forge authorization codes. Successful exploitation can lead to the creation of admin-capable access tokens, resulting in privilege escalation.
AnalysisAI
Authorization code forgery in Red Hat Keycloak enables unauthenticated attackers to escalate privileges to admin-level access tokens. The SingleUseObjectProvider's lack of type and namespace isolation permits attackers to forge valid authorization codes remotely, though exploitation requires high complexity (AC:H). No public exploit identified at time of analysis, with CVSS 7.4 indicating high confidentiality and integrity impact but no availability disruption.
Technical ContextAI
Keycloak is Red Hat's open-source identity and access management solution implementing OAuth 2.0, SAML 2.0, and OpenID Connect protocols. The vulnerability resides in the SingleUseObjectProvider component, a global key-value store used for tracking single-use tokens like authorization codes and nonces. The flaw represents CWE-653 (Insufficient Compartmentalization), where the provider fails to properly isolate objects by type and namespace. This architectural weakness allows attackers to manipulate the authorization code flow-a critical OAuth 2.0 mechanism where temporary codes are exchanged for access tokens. Without proper isolation, an attacker can craft malicious entries in the global store that the token endpoint accepts as legitimate authorization codes, bypassing the standard authentication flow entirely. The affected CPE indicates all versions of Red Hat Build of Keycloak are potentially vulnerable, suggesting this is a fundamental design issue rather than a localized code defect.
RemediationAI
Organizations should immediately consult Red Hat's security advisory at https://access.redhat.com/security/cve/CVE-2026-4282 for official patching guidance and affected version specifics. As of this analysis, no independently confirmed patched version number is available in the provided data sources, indicating this may be a recently disclosed vulnerability with patches pending or under embargo. Monitor Red Hat's Customer Portal and the Bugzilla ticket at https://bugzilla.redhat.com/show_bug.cgi?id=2448061 for updated remediation instructions and fixed builds. Interim risk mitigation strategies should include network segmentation to restrict Keycloak server accessibility to trusted networks only, implementing additional network-layer authentication for token endpoints, and enabling comprehensive audit logging for authorization code issuance and token generation to detect anomalous patterns. Review and minimize the number of admin-privileged service accounts and implement strict monitoring for new admin token creation. If possible without breaking functionality, consider temporarily restricting authorization code flow grants to only essential clients until patches are deployed.
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Session fixation in Keycloak's login-actions endpoints allows remote attackers to hijack authenticated sessions and take
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Same weakness CWE-653 – Improper Isolation or Compartmentalization
View allSame technique Privilege Escalation
View allVendor StatusVendor
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