Redhat: Security Vulnerabilities
A flaw was found in Keycloak. An authenticated administrator with the `manage-clients` role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to `realm-admin` for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.
CVSS Score
6.5
EPSS Score
0.002
Published
2026-05-28
A flaw was found in Keycloak's Client Policies, specifically within the `org.keycloak.protocol.oidc` component. When certain condition providers (client-type, client-roles, client-attributes, client-scopes) are used to enforce security restrictions, the `reject-ropc-grant` executor is silently bypassed. This allows an unauthenticated remote attacker to obtain tokens via a Resource Owner Password Credentials (ROPC) grant, even when a policy is explicitly configured to block it. This bypass can lead to unauthorized access and information disclosure.
CVSS Score
6.5
EPSS Score
0.003
Published
2026-05-28
A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements.
CVSS Score
5.9
EPSS Score
0.001
Published
2026-05-28
A flaw was found in Keycloak. A remote, unauthenticated attacker can exploit this vulnerability by sending specially crafted SOAP requests to the SAML ECP (Security Assertion Markup Language Enhanced Client or Proxy) endpoint with varying client IDs. By observing distinct faultstrings in the responses, the attacker can determine the client's protocol type, leading to information disclosure.
CVSS Score
5.3
EPSS Score
0.003
Published
2026-05-28
A flaw was found in Keycloak. An authenticated user with existing organization membership can exploit this flaw by accessing user-facing APIs, such as the account API or by requesting an OpenID Connect (OIDC) token with the 'organization' scope. This allows organization metadata to be disclosed in tokens, even after an administrator has explicitly disabled the Organizations feature, potentially leading to incorrect authorization decisions by resource servers.
CVSS Score
4.3
EPSS Score
0.002
Published
2026-05-28
A flaw was found in Keycloak. An authenticated user with low privileges can exploit this vulnerability by sending an oversized subject_token JSON Web Token (JWT) to the TokenEndpoint. When the token exceeds a 4000-character limit, it is silently dropped, causing the system to fall back to client credentials. This allows the user to gain the permissions of the client's service account, leading to privilege escalation.
CVSS Score
6.8
EPSS Score
0.003
Published
2026-05-27
A flaw was found in Samba’s handling of NTFS-style reparse points on shares configured with read only = yes. Due to missing SMB-layer access checks, authenticated users with underlying filesystem write permissions may create or delete reparse point metadata through SMB operations even on read-only exports. This could allow modification of SMB-visible file behavior, including converting files into symbolic links or other reparse point types.
CVSS Score
7.1
EPSS Score
0.008
Published
2026-05-27
A flaw was found in Samba’s vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share could overwrite a protected file by renaming a newly created file over the existing WORM-protected file.
CVSS Score
6.5
EPSS Score
0.009
Published
2026-05-27
A flaw was found in Keycloak, an open-source identity and access management solution. When a client application is configured to accept broad redirect Uniform Resource Identifiers (URIs), a remote attacker can manipulate the authentication process by crafting a special web address. If a user clicks this link, the client application might incorrectly prioritize attacker-controlled information over legitimate data. This vulnerability, known as HTTP parameter pollution, could allow an attacker to bypass security measures or gain unauthorized access to resources.
CVSS Score
4.2
EPSS Score
0.002
Published
2026-05-27
A flaw was found in Samba’s certificate auto-enrollment Group Policy handling. When certificate auto-enrollment is enabled, Samba may retrieve a CA certificate over an unencrypted HTTP connection and install it into the local trust store without proper verification. An attacker with the ability to intercept or redirect network traffic could exploit this behavior to supply a malicious certificate authority certificate, potentially allowing interception or spoofing of trusted communications.
CVSS Score
8.0
EPSS Score
0.003
Published
2026-05-27