While grammatically the former one seems to be the only correct form (English is my second language, so let me know if I'm wrong here), the latter one appears to be used quite extensively, and I wonder if it's appropriate, too. Thanks!
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This is a common mistake of (mainly native speakers) today to use adjectives in this improper way, as in your example. There's no grammatical reason to do so, but unfortunately it's happening more and more, even in mainstream media, TV, radio, etc.
I'm adding a quotation from an article called "Do it Real Quick, Or The Death of the Adverb". Beware that I do not necessarily agree with the whole article (in case you decide to read it), but I definitely agree with this quoted part:
Perfect has been used as adverb since the fifteenth century, but such use is now non-standard.