For those using older version of this, it is recommended they upgrade to the latest version now:
"Since the beginning of the year, Adobe Reader 8.1.1 and earlier versions have been susceptible to the Zonebac Trojan horse. Zonebac has the ability to wipe out your AV and changes search results. The same Trojan affected RealPlayer. It appears to be virtually undetectable so do not hesitate, immediately upgrade your Adobe reader to Adobe Acrobat 8.1.2".