Websense(R) Security Labs(TM) has discovered emails that claim to solicit humanitarian support for flood victims in the state of Tabasco, Mexico. If users click an embedded link, they are prompted to download a banker Trojan horse, disguised as an HTML file. The file is displayed with the blue Internet Explorer icon. When a user opens the file, the Trojan horse modifies the hosts file to replace the legitimate Banamex with the IP address of a host controlled by the attacker.

If users attempt to go to the Banamex site, they receive no visual indicators that they are not at a legitimate site. The phishing toolbars that were tested did not detect this fake site as a fraud. Neither the downloaded banker Trojan horse nor the subsequent executable that it drops (win32.exe) are detected as malicious by the 32 anti-virus products tested.

Websense Security customers are protected from this threat.

For additional details and information on how to detect and prevent this type of attack: http://www.websensesecuritylabs.com/alerts/alert.php?AlertID=824