Signature Forgery

Why
Signature forgery is important because it allows other people to pose as us and send messages that may be damaging

What
Signature forgery is the process of creating a valid digital signature for a given plaintext message

Existential Forgery
We can perform an easy but trivial type of signature forgery in the following way:

Because the Verify function in the digital signature system takes digital signatures and converts them to plaintext messages, we trivially get a valid message-signature pairing

Recognizability
We can solve the problem of existential