ICQ Inc. (formerly Mirabilis) ICQ 2003a, 2003b, Lite 4.0, Lite 4.1, and possibly other Windows versions allows user-assisted remote attackers to hide malicious file extensions and bypass Windows security warnings via a filename that ends in an assumed-safe extension such as JPG, and possibly containing other modified properties such as company name, icon, and description, which could trick a user into executing arbitrary programs.