Windows 2003/XP/2000/NT/ME/98/95

Delf.AHB is a backdoor that allows hackers to gain remote access to the affected computer in order to carry out actions that compromise user confidentiality and impede the tasks performed on the computer.

It captures certain information entered or saved by the user, with the corresponding threat to privacy: passwords saved by certain Windows services; email addresses.

It sends the gathered information to a remote user by any available means: email, FTP, etc.

It causes information loss: it indiscriminately deletes random files.

It reduces the security level of the computer: it notifies the attacker that the computer has been compromised and is ready to be used maliciously.

Delf.AHB uses the following propagation or distribution methods:

• Exploiting vulnerabilities with the intervention of the user: exploiting vulnerabilities in file formats or applications. To exploit them successfully it needs the intervention of the user: opening files, viewing malicious web pages, reading emails, etc.
• Via Internet, exploiting remote vulnerabilities: attacking random IP addresses, in which it tries to insert a copy of itself by exploiting one or more vulnerabilities.
• Instant messaging: it sends links pointing to a copy of itself to all users included in the infected user's contacts list.