What is Snowshoe spamming?
Snowshoe spamming is so named because the spammers distribute its email from various IP addresses with rotating domains in order to avoid detection and getting blacklisted. It is named after the use of snowshoes, in which snowshoes distribute a person’s weight over a wide area to avoid sinking into the snow. In a similar sense, Snowshoe spam distributes its email over a wide area to avoid email spam filters.
Email marketing services typically make money from affiliate programs and will send emails as part of email marketing campaigns. In 2003, the CAN SPAM Act requires that the email spam recipients are given an option of opting out. In the US many email marketing services will push the law to its limit and yet be compliant. So the key for email spammers is to comply with all opt-out requests but still be able to send more spam mail without violating the law. In contrast in many other countries, their law requires email recipients to opt-in before they can be sent marketing emails. The opt-in option makes legitimate email spamming more difficult.
Email marketing services that uses Snowshoe spam differs from illegal spammers. Even though email marketing services are spamming, they are legal as long as they comply with the law’s opt-out option. Some differences between the two are:
- Illegal spam does not provide an opt-out option whereas Snowshoe spam usually does.
- Illegal spam maybe sent from forged addresses whereas Snowshoe spam is not.
- Illegal spam will send all type of content such as gambling, x-rated spam, pharmaceuticals, etc and its message can be illegal or questionable. Snowshoe spam content does look legitimate.
- Illegal spam sends to everyone. Snowshoe spam tends to be at a more targeted of set of recipients.
Snowshoe spams are similar to solicited bulk mail, which is legitimate bulk mail. While solicited bulk mail is legal, snowshoe spam seem a bit on the shady side:
- Both types of email have similar visible content, but snowshoe spam is constantly adjusting the content in order to avoid filters.
- The domains in solicited bulk mail are fairly constant, but snowshoe spam constantly rotates through the domains.
- Solicited bulk mail sends from a stable group of sending IP addresses, but snowshoe spam is constantly rotating through them in order to evade detection.
The volume of Snowshoe spam varies. In cases where it is a big problem, responding to the opt-out option does not seem to make any difference. The opt-out links are questionable for many reasons:
- They may not work.
- Even when Snowshoe spammers honor the opt-out option on one list, they just add people into another mailing list.
- It is a matter of trust, often people just don’t trust the opt-out option work.