Zitadel /saml-post Endpoint XSS Vulnerability Analysis
A critical XSS vulnerability in Zitadel's /saml-post endpoint allows account takeovers via malicious scripts. The PoC highlights the need for immediate defensive measures.
CVE References
Affected
The /saml-post endpoint in Zitadel improperly handles user-supplied parameters, allowing injection of arbitrary JavaScript. This occurs due to lack of input sanitization and HTML encoding, enabling malicious scripts execution.
The PoC demonstrates a straightforward exploit for account takeover, proving the severity of unmitigated XSS flaws. It reliably exploits under normal usage conditions, making it highly dangerous.
Monitor for requests to /saml-post containing javascript: URLs or unexpected parameters, and look for unusual activity in logs, such as multiple failed login attempts or script execution warnings.
Sanitize and validate all user inputs on the /saml-post endpoint and implement output encoding to prevent raw HTML rendering. Apply rate-limiting to the endpoint and consider temporary access restrictions until patched.
High likelihood of exploitation due to critical impact and known PoC. Targets users with SAML integration, making it attractive for attackers aiming for high-value data.
Sources