Researchers at Symantec report that they've seen a spike in spam over the last six weeks, driven in part by traditional pharmaceutical themed messages, and also by a rather new technique, that being, blank e-mails.
That's right, having exhausted (seemingly) every angle on erectile dysfunction, having used every variation of celebrity video site, spammers are currently using blank messages sent to end users merely to verify the existence of their e-mail addresses to keep the spam waters churning, reports Symantec researcher Samir Patel.
The "blank body" messages are specifically being used by spammers in an attempt to locate valid/existing e-mail addresses within specific domains (I smell a spear phish) which is also known as a "directory harvest attack," or "DHA," the researcher notes.
The spam samples cited by Symantec offer a blank message body with a blank subject line, and no URLs or attachments, he said. The sender e-mail address is typically spoofed, though the examples offered by the company might be easier for some users to discern as they use gibberish e-mail addresses that are clearly questionable.
However, if someone starts spoofing real e-mail addresses, say those located in a contact's e-mail address book, one could see how the empty e-mails might have a pretty interesting effect. It's hard to look for social engineering cues when there really are none. And who among us hasn't mistakenly hit "send" before actually typing their message?
One can imagine that once spammers have observed the blank notes being opened, they likely begin sending more traditional spam attacks to the involved e-mail accounts.
In addition to this ghostly approach, Symantec reports that scads of more traditional, pharmaceutical-oriented e-mails are being passed around, this time with the predictable ED pill advertisements being buried in image attachments sent in nonsense news themed messages.
The jpg, jpeg, png, zip, and rtf file driven image spam tries to goad users into clicking on links to buy Viagra, or visit more generic online pharmacy sites, Patel said. Despite the fact that such campaigns have been around forever, they are contributing to a sizeable surge in overall spam trends of late, the expert said.
The e-mails tend to employ random subject lines that are obfuscated, misspelled, or even meaningless, such as "Coach Stops Runawway Horse by Biting Ear," but this hasn't stemmed their overall success rates, he noted.
Symantec has also observed large numbers of spam samples containing malicious attachments where the e-mail is positioned as a phony delivery failure notification from a reputed money transfer/parcel service, including some where the involved attachment is pitched as a copy of an invoice.
"In this pathetic effort of spreading malicious code, the spammer requests that recipients print out the attached invoice, which is actually an executable (.exe) file," Patel reports.
Whether utilizing engineering-free attacks or extremely hackneyed platforms, it's clear that spammers continue to keep the ball rolling. But hey, if this money making scheme ain't broke, why would they ever stop to fix it?
Matt Hines has been following the IT industry for over a decade as a reporter and blogger, and has been specifically focused on the security space since 2003, including a previous stint writing for eWeek and contributing to the Security Watch blog. Hines is currently employed as marketing communications manager at Core Security Technologies, a Boston-based maker of security testing software. The views expressed herein do not necessarily represent the views of Core Security, and neither the company, nor its products and services will be actively discussed in the blog. Please send news, research or tips to SecurityWatchBlog@gmail.com.