fraudulent

[1]	fake , counterfeit , forged , false , falsified , spurious , imitation , sham , pinchbeck , (Colloq) phoney/(US) phony
[2]	deceitful , dishonest , criminal , deceptive , tricky , artful , crafty , double-dealing , duplicitous , shifty , guileful , sharp , (Colloq) shady , crooked , bent

adj.

[1]	deceitful , fallacious