Keycloak up to version 6.0.0 allows the end user token (access or id token JWT) to be used as the session cookie for browser sessions for OIDC. As a result an attacker with access to service provider backend could hijack user’s browser session.

SQL Injection exists in MailSherlock before 1.5.235 for OAKlouds allows an unauthenticated user to extract the subjects of the emails of other users within the enterprise via the select_mid parameter in an letgo.cgi request.

The SAML broker consumer endpoint in Keycloak before version 4.6.0.Final ignores expiration conditions on SAML assertions. An attacker can exploit this vulnerability to perform a replay attack.

A flaw was found in JBOSS Keycloak 3.2.1.Final. The Redirect URL for both Login and Logout are not normalized in org.keycloak.protocol.oidc.utils.RedirectUtils before the redirect url is verified. This can lead to an Open Redirection attack

A flaw was found in Keycloak 3.4.3.Final, 4.0.0.Beta2, 4.3.0.Final. When using 'response_mode=form_post' it is possible to inject arbitrary Javascript-Code via the 'state'-parameter in the authentication URL. This allows an XSS-Attack upon succesfully login.

A flaw was found in Keycloak 4.2.1.Final, 4.3.0.Final. When TOPT enabled, an improper implementation of the Brute Force detection algorithm will not enforce its protection measures.

It was found that SAML authentication in Keycloak 3.4.3.Final incorrectly authenticated expired certificates. A malicious user could use this to access unauthorized data or possibly conduct further attacks.

It was found that the keycloak before 2.3.0 did not implement authentication flow correctly. An attacker could use this flaw to construct a phishing URL, from which he could hijack the user's session. This could lead to information disclosure, or permit further possible attacks.

It was found that when Keycloak before 2.5.5 receives a Logout request with a Extensions in the middle of the request, the SAMLSloRequestParser.parse() method ends in a infinite loop. An attacker could use this flaw to conduct denial of service attacks.

It was found that while parsing the SAML messages the StaxParserUtil class of keycloak before 2.5.1 replaces special strings for obtaining attribute values with system property. This could allow an attacker to determine values of system properties at the attacked system by formatting the SAML request ID field to be the chosen system property which could be obtained in the "InResponseTo" field in the response.