We received a couple of reports about Microsoft's "Smart Screen" flagging harmless sites as malicious. Initially, we considered the possibility of an infected ad service. But it may be a bug in Smartfilter as well. Some reports on twitter [1] show that the problem has been resolved.

Please let us know if you have sample URLs that are still affected.

To disable smart screen: Select "Internet Options" from the "Tools" menu. Select the "Advanced" tab and find the "Enable SmartScreen Filter"  setting (about the 10th item from the bottom. Scroll all the way down). Needless to say: This will also remove the smart screen protection from real-evil sites, not just from appear-to-be-evil-to-smartscreen-today sites. The setting should only be changed if you can't wait for the problem to be fixed.

[1] http://twitter.com/#!/search/%23smartscreen

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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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