Benne de Weger
More info
- Affiliation
- TU Eindhoven
- Known for
- Colliding X.509 certificates, the 2008 rogue CA
Dutch mathematician who helped show that an MD5 collision was not a curiosity but a way to become a certificate authority.
At TU Eindhoven de Weger worked with Arjen Lenstra and then-PhD student Marc Stevens. In 2007 the three presented the first chosen-prefix collision for MD5 and used it to build two X.509 certificates with different names but the same signature.
In December 2008 they went further at 25C3 in Berlin, joined by Alexander Sotirov, Jacob Appelbaum and others. Using a cluster of around 200 PlayStation 3s, they obtained a certificate RapidSSL signed as an ordinary website certificate, whose colliding twin was a valid CA certificate. CAs dropped MD5 within weeks; that it took a demonstration rather than four years of warnings says something about the industry.