A sender S sends a message m to receiver R, in which the message digest is digitally signed by S with its private key. In this scenario, one or more of the following security violations can take place.
(I) S can launch a birthday attack to replace mm with a fraudulent message.
(II) A third party attacker can launch a birthday attack to replace mm with a fraudulent message.
(III) R can launch a birthday attack to replace mm with a fraudulent message.
Which of the following are possible security violations?
(A) (I) and (II) only
(B) (I) only
(C) (II) only
(D) (II) and (III) only
Acoording to the original question https://gateoverflow.in/118295/gate2017-1-15 @shivnash is considering whole message is encrypted which is case 1 and then arrived at the answer as option B
what if it was case 2 the answer is still the same?
