What is the CVSS score of CVE-2026-4628?

CVE-2026-4628 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Red Hat are affected by CVE-2026-4628?

Organizations using A flaw should be aware of moderate risk from CVE-2026-4628, a improper access control vulnerability rated CVSS 4.3.

How to fix or mitigate CVE-2026-4628?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Red Hat CVE-2026-4628

EUVD-2026-14389 MEDIUM

Improper Access Control (CWE-284)

2026-03-23 redhat

GHSA-4pgc-gfrr-wcmg

Authentication Bypass Red Hat

4.3

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

4.3 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Red Hat

4.3 MEDIUM

qualitative

Primary rating from NVD.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Lifecycle Timeline

EUVD ID Assigned

Mar 23, 2026 - 08:45 euvd

EUVD-2026-14389

Analysis Generated

Mar 23, 2026 - 08:45 vuln.today

CVE Published

Mar 23, 2026 - 08:09 nvd

MEDIUM 4.3

Blast Radius

ecosystem impact

† from your stack dependencies † transitive graph · vuln.today resolves 4-path depth

47 maven packages depend on org.keycloak:keycloak-services (15 direct, 32 indirect)

Ecosystem-wide dependent count for version 26.6.0.

DescriptionCVE.org

A flaw was found in Keycloak. An improper Access Control vulnerability in Keycloak’s User-Managed Access (UMA) resource_set endpoint allows attackers with valid credentials to bypass the allowRemoteResourceManagement=false restriction. This occurs due to incomplete enforcement of access control checks on PUT operations to the resource_set endpoint. This issue enables unauthorized modification of protected resources, impacting data integrity.

AnalysisAI

Keycloak's User-Managed Access endpoint fails to properly enforce access control on PUT operations, permitting authenticated attackers to modify protected resources despite the allowRemoteResourceManagement restriction being disabled. This access control bypass affects data integrity and impacts any organization using Keycloak for identity and access management. The vulnerability requires valid credentials to exploit and currently has no available patch.

Technical ContextAI

The vulnerability resides in Keycloak's User-Managed Access (UMA) implementation, specifically in the resource_set endpoint that manages user-controlled resource definitions within the OAuth 2.0 and OpenID Connect authorization framework. The flaw is classified as CWE-284 (Improper Access Control), indicating incomplete enforcement of authorization checks on HTTP PUT operations to the resource_set endpoint. Keycloak, which serves as an identity and access management (IAM) platform across Red Hat products including JBoss Enterprise Application Platform 8 (cpe:2.3:a:red_hat:red_hat_jboss_enterprise_application_platform_8:*:*:*:*:*:*:*:*), Red Hat Single Sign-On 7 (cpe:2.3:a:red_hat:red_hat_single_sign-on_7:*:*:*:*:*:*:*:*), and Red Hat Build of Keycloak (cpe:2.3:a:red_hat:red_hat_build_of_keycloak:*:*:*:*:*:*:*:*), implements UMA 2.0 protocol features where resource owners should have restricted capabilities when allowRemoteResourceManagement is disabled. The root cause appears to be missing or insufficient validation logic at the authorization layer for PUT operations, allowing authenticated users to circumvent policy restrictions that should prevent remote resource modification.

RemediationAI

Upgrade Keycloak and affected Red Hat products to the patched version released by Red Hat addressing CVE-2026-4628; refer to https://access.redhat.com/security/cve/CVE-2026-4628 for specific version numbers and release dates. Until patching can be completed, implement the following interim mitigations: disable or restrict the UMA resource_set endpoint via reverse proxy rules for non-administrative users, enforce allowRemoteResourceManagement=false at the configuration level with additional API gateway-level authorization checks, restrict network access to Keycloak administrative and UMA endpoints to trusted internal networks only, and audit resource_set modification logs regularly to detect unauthorized access attempts. Organizations should also review and implement the principle of least privilege for all service accounts interacting with the UMA endpoints.