SAML authentication bypass via Incorrect XPath selector

Ruby-SAML in = 12.2 and 1.13.0 = 1.16.0 does not properly verify the signature of the SAML Response. An unauthenticated attacker with access to any signed saml document by the IdP can thus forge a SAML Response/Assertion with arbitrary contents. This would allow the attacker to log in as arbitrar...