E-mail Hell

I’ve got to get my e-mail filtering system back in place.

I’m not being overwhelmed by spam as much as a lot of other people — I only get maybe a dozen pieces of spam a day. It’s still the majority of mail that I recieve though, and they’re getting sneaky enough to use subject lines that make you hesitate and think it just might be relevant, especially when you run a web site. You get a piece of e-mail with the subject “I think this link is broken” only to find out it’s for GENERIC VIAGRA CHEAP! when you open it…

Unfortunately spam is getting trickier to filter out no thanks to things like the use of HTML in e-mail. HTML was never meant for e-mails, but some wiseguys got the idea of making it show up in mail readers if it happened to be present, which encouraged people to use it, which made e-mail client explicitly allow composing in it… Unfortunately, HTML allows things like:

1) Obscuring the real text of the message

I wish you could filter our just on specific words like “Viagra”, but that doesn’t work anymore due to embedded HTML comments. Although on your screen it might show up as all one word, within the raw text it actually looks something like

Vi<!--fdsatfrqrf-->a<!--gehjwghk-->gr<!--iouwhjlkh-->a

They specifically try to block matching against words by inserting random HTML comments all over the place.

2) Tracking your usage

Some e-mails are now including ‘invisible’ images which link back to a website run by whoever sent the spam. As soon as you open it, if your mail client automatically loads HTML data, it contacts the web site and presto, the company now knows that you actually opened the e-mail. E-mail addresses that are verified to be valid are considered more valuable than unverified addresses. Expect to get a lot more spam sent your way…

Time to start tuning those filters a bit more…