NWA-PCUG Newsletter Article, September 2003
More on SPAM – Bane of the Internet
by Ira Wilsker
(click to email author)

Recently, here in the Examiner, I wrote about the report from the Federal Trade Commission (FTC) citing the prevalence and deception common in “unsolicited commercial email”, more commonly referred to as “spam”.

According to a report recently published by Ferris Research, it is estimated that spam will cost American businesses over $10 billion this year, considering computing resources, labor costs, and lost productivity. According to the email filtering service Brightmail, in the month of March 2003, 45% of all email was spam, compared to only 16% in January 2002, a 181% increase!

The FTC has created a website with good information on spam, including tips on reducing the volume received, as well as ideas on preventing spam. This site is online at http://www.ftc.gov/spam, and contains much helpful information.

As has been stated previously in this column, email addresses are typically harvested from websites, newsgroup postings, chat rooms, and other sources. Many web merchants also sell lists of customers, and there are also some Internet Service Providers (ISPs) and email providers that sell subscriber lists. Many of the free email subscription services offering jokes, recipes, news, and other information, support themselves by selling subscriber information. Many software publishers sell lists of registered users. Some viruses, worms, Trojans, and spyware may harvest the users’ personal email addresses, and possibly even hijack an address book. Once harvested, email addresses, often millions of them, are compiled and sorted, and then sold and resold countless times.

Some spam mail is sent using even more insidious means, such as by software installed by some of the popular file sharing programs, concealing the real source of the spam. Another method, recently reported on securityfocus.com, in an article “Rise of the Spam Zombies”, is the rapidly spreading use of worms and viruses as a means of sending spam mail from infected computers. One especially nasty Trojan is the “Proxy-Guzu”, which makes the infected computer and Internet connection available to spammers, who can then send spam from that computer, again obscuring the real source. If the source is traced, it will point back to the infected computer. “Proxy-Guzu” may be installed on the victims’ computers after the users open emails claiming to have images from an “adult” webcam, or other forms of pornography. Another backdoor Trojan worm, “Jeem”, has been around for about a year, and enables unauthorized access to the victims’ computers for the purpose of “laundering” spam email, again making the true source undetectable, and showing the source as the infected computers. This again emphasizes the oft-stated necessity to have updated antivirus software installed, as well as the need for a firewall and anti-spyware software.

The FTC has suggestions on making your email address less vulnerable to harvesting. The FTC suggests that your email addresses not be posted to the public. Many users have public email addresses used on websites, newsrooms, and chats, and private email addresses only given to family and trusted friends, but never publicly used. Another FTC suggestion is to be careful about submitting your email address to a web merchant or other website; read the sites’ privacy statements, being sure that your email address will not be sold or used for other purposes. Refuse to give your email to any site that will not protect it, and opt-out of any sites that have previously been joined. Of course, once an address is available and harvested, it can never be totally removed from spam lists. If a site with a privacy policy also offers to share your information with “selected partners”, be sure to refuse such sharing.

Many ISPs now offer some form of email filtering, which can offer a varying quality of protection from spam (and viruses). If your ISP offers it, sign up for it; some ISPs offer active filtering, while others simply subscribe to one of the many “blacklists” that block emails from all senders in a block of addresses. Many blacklists also stop large amounts of legitimate email along with the spam, and often block innocent senders who are blacklisted, as 46% of spam (according to the FTC) has forged “From:” headers.

There are now many spam filtering software products that can be installed on personal computers. Some are from the leading antivirus publishers and other major software publishers, and others are independently produced. Much of the technology is immature, and some of the products are of dubious utility, but most offer some degree of protection from spam. I have tried several, and had mixed results, none being totally accurate. The highest success rate I found when experimenting with spam filters was the commercially available Brightmail service. Brightmail is no longer available directly to individuals (used to be free), but many ISPs subscribe to its service. Emails are routed through the Brightmail server, where each message is electronically scanned for spam, and sorted. “Clean” email is forwarded to the subscriber, and the email filtered out is available on the Brightmail site for a limited period, where the user can inspect it, and approve it for receipt, if desired.

Federal legislation controlling spam is making its way through Congress, but there is a powerful lobby resisting the measure. Federal legislation will also be ineffective in stopping spam from foreign sources, but something needs to be done to decrease the rate of spam. Some pundits are currently calling spam the biggest threat to the Internet, even worse than viruses, worms, and Trojans.

There is no restriction against any non-profit group using this review as long as it is kept in context with proper credit given the author. This review is brought to you by the Editorial Committee of the Association of Personal Computer User Groups (APCUG), an international organization of which this group is a member.

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