MaxKey contains an unauthorized access vulnerability due to a hard-coded JWT signing secret in application-maxkey.properties that allows unauthenticated attackers to forge valid JWT tokens and authenticate as any user by exploiting the password-skipped login endpoint. Attackers can craft a JWT token signed with the publicly known default secret, submit it to the /sign/login/jwt/trust endpoint, and obtain a fully authenticated admin session with access to SSO application configuration and downstream application secrets.

MaxKey through 4.1.12, fixed in commit ddbb72f, contains an insufficient redirect URI validation vulnerability in DefaultRedirectResolver.hostMatches() that allows remote attackers to hijack OAuth 2.0 authorization codes by supplying a crafted redirecturi whose hostname suffix matches a registered URI without proper dot-boundary anchoring. Attackers who control a domain ending with the registered redirect URI hostname can social-engineer victims into clicking a crafted authorization URL, causing the authorization code to be issued to the attacker-controlled URI and exchanged for an access token granting access to the victim's identity.

A vulnerability was found in Dromara MaxKey up to 4.1.7 and classified as critical. This issue affects the function Add of the file maxkey-webs\maxkey-web-mgt\src\main\java\org\dromara\maxkey\web\apps\contorller\SAML20DetailsController.java of the component Meta URL Handler. The manipulation of the argument post leads to server-side request forgery. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.