Automatic and Precise Client-Side Protection against CSRF Attacks

A common client-side countermeasure against Cross Site Request Forgery (CSRF) is to strip session and authentication information from malicious requests. The difficulty however is in determining when a request is malicious. Existing client-side countermeasures are typically too strict, thus breaking many existing websites that rely on authenticated cross-origin requests, such as sites that use third-party payment or single sign-on solutions. The contribution of this paper is the design, implementation and evaluation of a request filtering algorithm that automatically and precisely identifies expected cross-origin requests, based on whether they are preceded by certain indicators of collaboration between sites. We formally show through bounded-scope model checking that our algorithm protects against CSRF attacks under one specific assumption about the way in which good sites collaborate cross-origin. We provide experimental evidence that this assumption is realistic: in a data set of...

• Type: Journal
• Year: 2011
• Where: ESORICS
• Authors: Philippe De Ryck, Lieven Desmet, Wouter Joosen, Frank Piessens
• Keywords: Collaboration Scenarios, Csrf, Design Implementation, ESORICS 2011, Security Privacy