Hi all, Today I announce the construction of a valid X.509 certificate, based on the MD5 hash function, that allows two different digital signatures on the (identical) "to-be-signed" part. This is based on a new technique of constructing MD5-anti-collisions. For details, see http://www.win.tue.nl/~bdeweger/AntiCollidingCertificates/.
This type of certificate is called "anti-colliding", as this is complementary to a construction, announced one month ago, of "colliding x.509 certificates", i.e. two different X.509 certificates with identical signatures, based on MD5-collisions. See http://www.win.tue.nl/~bdeweger/CollidingCertificates/. Grtz, Benne de Weger
