OAuth Server vulnerabilities

The OAuth Server plugin in versions up to and including 4.5.1 contains a Cross Site Scripting (XSS) vulnerability exploitable by a user with Contributor privileges. This enables injection of a malicious script into the site.

A flaw was found in the oauth-server component. This open redirect vulnerability occurs when the 'then' parameter in the grant approval handler is not properly validated. A remote attacker can craft a malicious URL that, when approved or denied by an authenticated user, redirects them to an attacker-controlled website, enabling phishing attacks.

A vulnerability in the OAuth-server causes OAuth2 client secrets to be logged when the log level is set to Debug or higher for OIDC/GitHub/GitLab/Google login options.