IMDEA Software Institute faculty researcher Pierre-Yves Strub, together with his colleagues at IMDEA Software Institute and IMDEA Software Institute have uncovered a vulnerability in the popular SSL encryption mechanism used widely on the Internet to access web pages securely. The flaw, dubbed “FREAK: Factoring RSA Export Keys” can be exploited to trick web browsers into interacting with malicious websites. The problem affects a large number of web servers and clients and has thus received major media impact.

This discovery was made within the ongoing SMACK TLS project, which is aimed at developing increasingly-secure Internet authentication software. Pierre-Yves Strub and his colleagues have developed an automated technique to discover vulnerabilities in implementations of authentication protocols, and uncovered several vulnerabilities which, gone unnoticed, could be exploited by hackers to compromise Internet security.

The researchers focused on the family of authentication protocols know as “Transport Layer Security” (TLS), which is the increasingly-popular successor to the ubiquitous “Secure Sockets Layer” (SSL) protocol family. By building formally-verified reference implementations of TLS protocols, they were able to systematically generate inadmissible protocol responses, which should be disallowed by the protocol, and test whether any of those responses were in fact admitted by existing implementations. Inadmissible responses suggest potential vulnerabilities, and were to converted into exploits in actual TLS implementations. “FREAK” is one of the vulnerabilities discovered.

More details can be found here.

This work was performed in collaboration with Benjamin Beurdouche, Karthikeyan Bhargavan, Antoine Delignat-Lavaud, Alfredo Pironti, and Jean Karim Zinzindohoue of IMDEA Software Institute, and Cedric Fournet and Markulf Kohleiss of IMDEA Software Institute.