Identity Theft: Attacks on SSO Systems

Explore a critical vulnerability affecting SAML-based Single Sign-On (SSO) systems in this AppSecUSA 2018 conference talk. Delve into the newly discovered flaw impacting multiple independent SAML implementations and potentially any system relying on XML signature security. Learn how attackers can exploit this vulnerability to tamper with signed XML documents, modifying attributes like authenticating users without invalidating signatures. Understand the root cause stemming from XML DOM traversal methods post-signature validation. Discover how this vulnerability allows authenticated attackers to access services as different users. Additionally, examine a related class of user directory vulnerabilities that can amplify the impact or even enable authentication bypasses independently. Gain valuable insights from Kelby Ludwig, Principal AppSec Engineer at Duo, on these critical security issues affecting modern organizational trust anchors.