In the Bug Report forum, there’s a pinned thread…
REPORTING HACKS, CHEATS, AND EXPLOITS
Perhaps you should consider updating it, as it says that players can contact Nevalistis directly via email with details of hacks which are sensitive in nature. As Nevalistis left Blizzard three months ago, presumably that email address is no longer valid.
Should such reports now be going to FilthieRich, our newest CM?