(Michael Kassner, TechRepublic) There seems to be a run on e-mail induced malware lately. It seems that e-mail as a malware delivery vehicle is getting a second wind. E-mail attachments and links are popular methods for bad guys to install malware on computers. So it’s important to understand what to do when you get an e-mail that has an attachment or link in the e-mail message body.

E-mail attachments are files that accompany e-mail messages. Attachments can be one of two things:

1. The actual file or document designated in the e-mail.
2. A copy of the expected attachment that has malware embedded in it.

E-mail links are the underlined phrases in e-mail messages that simplify going to a specified Web site. Clicking on a link can cause one of three things to happen:

1. The link opens the correct Web page referred to in the email.
2. The link activates a malware program embedded in the e-mail message.
3. The link is spoofed. It opens a Web page similar to the correct page, but with malware embedded in it.

Activating malware
E-mail malware requires user intervention to get started. It’s that simple. The bad guys will try any method possible to entice you to open an attachment or click on a link. One of their favorite tricks is to pretend that the e-mail is from someone you know. That way you have no reason to be suspicious.

Spread to other computers
Once installed, the malware will immediately try to infect other computers by sending out e-mail messages with the same infected attachment to all the e-mail addresses it found on the newly-infected computer.
Those recipients will more than likely open the e-mail attachment as well, because it appears to be from someone they know. So it’s not hard to see that this process will quickly overrun every computer on the network