You don't need both 'attached' and 'herewith'. (I don't think it's appropriate to use 'herewith' in this context anyway, as there's no physical container [such as an envelope] with more than 1 thing in it, but if something's 'attached' it's bound to be 'herewith') . 2 is right for you. You might use 1 if you were attaching someone else's CV.
PS In extremely formal contexts, referring to physical things in a package, you might say 'attached hereto', but I wouldn't recommend it.