A session fixation issue was discovered in the SAML adapters provided by Keycloak. The session ID and JSESSIONID cookie are not changed at login time, even when the turnOffChangeSessionIdOnLogin option is configured. This flaw allows an attacker who hijacks the current session before authentication to trigger session fixation.

An open redirect vulnerability was found in Keycloak. A specially crafted URL can be constructed where the referrer and referrer_uri parameters are made to trick a user to visit a malicious webpage. A trusted URL can trick users and automation into believing that the URL is safe, when, in fact, it redirects to a malicious server. This issue can result in a victim inadvertently trusting the destination of the redirect, potentially leading to a successful phishing attack or other types of attacks. Once a crafted URL is made, it can be sent to a Keycloak admin via email for example. This will trigger this vulnerability when the user visits the page and clicks the link. A malicious actor can use this to target users they know are Keycloak admins for further attacks. It may also be possible to bypass other domain-related security checks, such as supplying this as a OAuth redirect uri. The malicious actor can further obfuscate the redirect_uri using URL encoding, to hide the text of the actual malicious website domain.

A vulnerability was found in Keycloak. This flaw allows attackers to bypass brute force protection by exploiting the timing of login attempts. By initiating multiple login requests simultaneously, attackers can exceed the configured limits for failed attempts before the system locks them out. This timing loophole enables attackers to make more guesses at passwords than intended, potentially compromising account security on affected systems.