DSL Extreme
Where are you? Support > Knowledge Base > FAQ's > Spam Information

Spam Information  

Spam Information
This document is intended to outline the ways in which spammers obtain your email address. Also included are methods one can use to try and prevent becoming the target of spam.
It must be stressed that DSLExtreme does NOT and NEVER WILL share ANY customer information with ANYONE, even if the customer no longer uses our services. We do not sell customer information, and we do not allow unethical network practices (spamming, hacking, spyware distribution, denial-of-service, etc.) via our services. When we receive an incident report of network abuse, we take it very seriously and do everything we can to correct the issue as quickly as possible.
Spam, by definition, is unsolicited/unwanted email. These can include virtually any type of content, and are not limited to commercial internet advertisements. Many spam messages can contain unwanted tracking cookies, pop-ups, spyware, and Trojans. Virtually all spam comes with a deceptive From: address, and is rarely the true address of the sender. The obvious thing you can do is simply to mark and delete them, but of course this does not let you avoid having to sift through them.
There are many ways spammers can obtain your email address, both without your knowledge, and by deceiving you into giving up your information yourself. Here's a few of the tricks they commonly use:
1. Spiderbots and web search This is probably the easiest method for a spammer to obtain email addresses. There are robot applications commonly called 'bots' that have the ability to hunt through the internet automatically, looking for anything even remotely resembling an email address. The addresses can be located just about anywhere you've posted them. If you enter your email address on a registration page on the web, post a message on a public message board, list the email address on your website, or even sign it on an outgoing email, there is a chance the bot will locate and harvest your email address. As an example, go to google.com, and enter "@dslextreme.com" into the search bar, with the quotes. You will see the results contain everything from official DSLExtreme sites to email addresses of customers who have posted public messages that include their email address. The term "spiderbot" comes from a bot capable of searching through multiple locations or search engines, or "spidering" the search request.
2. "Click here to unsubscribe"/replying to spam Easily the most successful email address harvesting method, since the spammer doesn't actually have to do anything to verify an email address. The seemingly innocuous "Click here to unsubscribe" link at the bottom of a spam item is a trap, as is replying to a spam item. This is not to say that legitimate mailing lists and newsletters contain a fraudulent "Click here to unsubscribe" link. If the spam was unsolicited, in other words - it was not anything you ever signed up for, then DO NOT "Click here to unsubscribe". Clicking the unsubscribe link or replying to the spam item will only confirm your email address to the spammer, and you will start receiving hugely increased volumes of spam, since the spammer, who now has your confirmed-working email address, sells your address to 5 more spammers. You can guess the result of that after your address gets passed along a few times.
3. Directory harvesting While being somewhat antiquated technology-wise, this email address harvesting method is prevented by how your Internet Service Provider has their mail servers configured. What happens is, the spammer will either bombard the mail server with a huge amount of email in the hope that any bad addresses will return an error, or will use server-level commands to verify the authenticity of an address. If the spammer does not receive an invalid address error from the mail server, the spammer assumes the email address in question is a valid one, and it gets added to the spam mailing list. DSLExtreme's mail servers are set up to prevent the directory harvesting method as much as possible.
4. Spyware In the last few years, the line between spam and worms/spyware/viruses (collectively known as "malware") has grown thinner. Malware developers and spammers alike have noticed the advantages in combining their efforts to try and ruin your day more effectively. Spam can now include links or attachments that will attempt to install a piece of malware on your system. Once the spyware has infected your system, it will almost always transmit your email address to a central database, and then either use your address to send out spam, or saturate your own mailbox with it. Spyware is quickly becoming more of a threat than viruses and worms since its designed specifically to collect otherwise-confidential information and disseminate it to whoever happens to be watching for that type of information. Most commonly, spyware gets installed without the user's knowledge, and is usually triggered by the user clicking on a link in a pop-up page or spam item.
The list goes on.
Ultimately, due to the saturation of spam on the internet (roughly 50% of all email sent today is spam), it is impossible to prevent spam with 100% effectiveness. If you're only using a single tool to try to block spam (a block sender command, email address blacklist, anti-spam filter, anti-spam application, etc.), chances are you will not block very many items. Spam filters are designed to track specific text strings in either the body of the email, the subject line itself, or source email addresses listed in the blacklist. Spammers find it easy to get around these by simply changing their spam text a bit. For example, you're trying to block gambling spam by adding a rule to block any subject line containing the text string "casino", yet, you still receive the spam. Entering the text string "casino" into your filter will only attempt to block items containing the exact text. If the spam's subject line contains "cas ino" and not "casino", the spam will get right through the filter. This also applies to email address filtering since the vast majority of all spam contains fake or forged From: addresses. You'll notice in many spam items the From: address contains gibberish anyway. If you're trying to block spam using a blacklist method, try blocking the entire domain instead of just a specific address.
The highest security available comes from creating or configuring a white list, or "approved senders" list. This will essentially block any email coming into your mailbox that isn't listed as an approved sender. The only drawback to this method, obviously, is the risk of blocking legitimate emails.
DSLExtreme's policy on spam can be found on our Terms & Conditions/Acceptable Use Policy page at - dslextreme.com/aup.php
If you have a spam complaint, you should send the spam item AS AN ATTACHMENT to [email protected], where our Network Abuse team will investigate the spam and attempt to notify the ISP shown as the source. If the spam is coming from an external source (a non-DSLExtreme user), there is very little we can do short of notifying the ISP who is in charge of the address, and hope their Network Abuse department takes care of it. In some cases, the ISP in question supports spam and spyware types of practices, or otherwise ignores spam complaints altogether. Thankfully those entities are in the minority, but we do run into them. They're usually responsible for a large number of complaints, and they will likely get blocked entirely from our network once discovered. If the spam is coming from an internal source (a DSLExtreme user), Network Abuse will process the complaint and notify the user directly.
For more detailed information on spam and malware, please visit the links below:
spamhaus.org - Spam/malware alert center, detailed international spam/malware trends, spam/malware distributor database, spam/malware abuse center and database.
declude.com - Spam control information and services, offline/online anti-spam tools, latest spam/malware threats, list of spam databases, and more
sarc.com - Symantec Antivirus Research Center Windows security advisories, worm/virus/Trojan/spyware databases, latest threat lists, removal tools, Norton product support.
fraudwatchinternational.com - Internet email scam/fraud trend monitoring, known scam/fraudulent email database, scam/fraudulent email examples and recognition.
If you have any further questions, you may contact our Network Abuse Department at either the email address or phone number below.
DSLExtreme Network Abuse Department
[email protected]


Search our Knowledge Base


Enter a Search Term: Or do an Advanced Search

Don't want to search? Go to our Knowledge Base directly

Send an Email to a Representative

Sales & Information

Have some pre-sales questions about our packages or features?

Billing Department

Have a question about your bill or upgrading your package?

Technical Support

Having problems with your Connection? Or setting up your email?


From Talia S.
  • @jank0 Wanted to thank @DSL Extreme