Phishers are disguising e-mails as electronic postcards from family in order to lure consumers to sites that deliver a malicious Trojan horse program to their computers.
The latest scheme to commandeer someone's computer to steal passwords, spread spam or attempt some other nefarious act was reported this week by The SANS Institute, a cooperative research and education organization.
The e-mail arrives as a postcard-pickup notification with a message that reads, "You have just received a virtual postcard from a family member!" Clicking on the link in the message sends the person to a site that uploads a Trojan that hijacks the computer's mIRC, which is a popular Internet Relay Chat program.
MIRC runs under Windows and provides a graphical interface for logging onto IRC servers and listing, joining and leaving chat channels.
Hooking a Trojan to an IRC program gives the malware an entry point that slides past most anti-virus engines and desktop firewalls. Many of these applications treat IRC programs as benign and allow them to operate, SANS said.
Because of the increasing sophistication of phishing attacks, the institute advises computer users to take no chances and refuse to accept nearly anything from the web.
"Without knowing the true source of an e-mail, one has to be cautious on accepting just about everything these days," the institute said.
Phishing e-mail campaigns have been growing in sophistication as phishers increase the variety of bait used to lure victims. Rather than depend solely on e-mail disguised as messages from national and regional banks, phishers are getting more creative in dressing up their messages.
For example, security experts last month reported seeing phishing attacks directed at Monster.com. A spoofed e-mail claiming to be from the job-posting site's customer service asked computer users to log in to check their personal information to avoid having their accounts suspended. The ploy is believed aimed at the companies that use Monster.com to search the database for resumes.
Traditionally, phishers directed people to a fake banking site, where they would be tricked into typing in their ID and passwords. Today, phishers attempt to trick people into downloading programs that will record keystrokes when they go to an e-commerce or banking site, and then send that information to the phisher.
In Brazil, for example, e-mail that pretended to contain a song sent by a family member and dedicated to the recipient actually contained a key-logging program, Dan Hubbard, a lead investigator with the security lab of Websense Inc., said Wednesday.
"(Phishers) are finding smarter ways to get onto your machine," Hubbard said. "The attackers are evolving."
San Diego-based Websense is a member of the Anti-Phishing Working Group, a coalition of technology companies and law enforcement agencies devoted to eliminating ID theft. Hubbard is a member of the APWG's management committee.
The number of phishing sites overall continues to grow. In February, the number climbed by about 2 percent over January, reaching 2,625 for the month, according to the APWG. The number of sites in China grew by 10 percent to account for 28 percent of all phishing scam sites, second only to the U.S.'s 37 percent. Korea is a distant third at 11 percent.