Interesting question.
First, its God that gave us a 'supposedly' free will, so everything, good and bad, can be laid at his door.
Second, in the Bible, Old Testament/Torah, (I haven't read The Quran, just bits), God is a selfish God, a Killer and Dictator.
Fourth, God is supposed to have created everything, so that also includes the Devil, and don't forget, Earth was given to him as his domain, by God.
I believe, that if, and its a big if, there really is a God, then he's not just evil, he's pure evil.