US-CERT has seen reports of an email attack targeting Microsoft's April Security Bulletin release cycle. This attack arrives via email messages with the subject line "Critical Patch Released: Microsoft Security Bulletin MS08-64738." These email messages contain a link to a fraudulent Microsoft Update web site that hosts malicious code or contains an attachment that is embedded with malicious code. Users who follow the link or open the attachment may become infected with a Trojan.

http://www.us-cert.gov/current/index...ng_microsoft_s