I emailed a senior person at CFA Institute and this was the reply: "I think the only way that using someone’s test questions would be a violation of the Code and Standards would be based on how the test questions were obtained. If they are, in fact, actual questions that were memorized by a candidate and then posted, or if someone had an actual exam that they somehow illegally obtained and then posted, I think both the poster and the user would be in violation of the Code. "