Sflash
Sflash is an asymmetric cryptosystem for digital signatures . It was developed by Nicolas T. Courtois, Louis Goubin and Jacques Patarin.
Sflash was recommended by the NESSIE project in 2003.
In 2007 Vivien Dubois, Pierre-Alain Fouque, Adi Shamir and Jacques Stern presented a full attack on Sflash. This is remarkable in that an algorithm recommended by an EU authority was completely broken within a few years.
The developers of Sflash then suggested changes to prevent the attack.