Limited Open redirection using SSO-SAML

Hello, **Endpoint:** https://hackerone.com/users//saml/[email protected]&remember_me=true Recently, you have patched an open redirection issue which was reported as #171398. I found a bypass of that patch. **Steps to reproduce:** 1. Add following in comment/report : ```https://hackerone.com/users//saml/[email protected]&remember_me=true``` 2. Click on link. 3. You will redirected on SSO URL without going through **External Link Warning** page. 4. Done. PoC : https://hackerone.com/users/saml/[email protected]&remember_me=true (Through external warning page) https://hackerone.com/users//saml/[email protected]&remember_me=true (Without external warning page) **Suggested Fix:** Use more stronger regular expression and filtration at this endpoint. Best regards, Shailesh