Flash ads that take over your clipboard

Attackers are now using Flash banner ads that take over your clipboard by forcing a malicious URL into it.

The Flash ad will keep the bad URL in the clipboard so that you won't be able to remove it until you close your browser. The URL leads to a fake antivirus program. The hope is you might accidentally go to that URL by pasting it onto your browser, or spam your friends on the attacker's behalf.

For a demo, go to security researcher Aviv Raff's demo page. The Flash object on that page will overwrite your clipboard with "http://www.evil.com" and keep it there until you close his page.

What to do about this:

If you have an AccessEnforcer, we highly recommend that you turn on web filtering and enable the Ads URL blacklist category -- which will block all sorts of ads including Flash ads.

We also recommend running Firefox with the NoScript extension. NoScript blocks Java, JavaScript, and Flash content unless the site is explicitly allowed (and is easier to use than it sounds).