According to the Forums Code of Conduct, under NO circumstances should a hack or exploit be reported on the public forums. Because of the sensitive nature of hacks/exploits, posting on forums only ensures that other people are going to attempt to use them. Any poster who breaks this rule will have his/her thread deleted immediately and may be reviewed for a forums suspension.
If you would like to report a hack, cheating, or other activity against the Terms of Use, please send a detailed e-mail to hacks@blizzard.com .
If you’ve discovered an in-game bug that you feel is sensitive in nature and may potentially be used to exploit game mechanics for personal gain, you may also feel free to contact me directly at nevalistis@blizzard.com with a full report of how to reproduce the issue. I’ll ensure that these details are sent to the development and quality assurance teams post-haste.
Thank you for your due diligence. Reporting these issues is incredibly important, but at the same time please remember it’s also important to report them through the appropriate channels.