The SPAM-L mailing list will be shut down as of May 11th, 2009.
Please read this post for more information and an explanation.
This FAQ will be kept indefinitely for historical purposes but updates will be rare, if they are made at all.
[Edit: Some folks have set up a successor to the list at http://spammers.dontlike.us/ (SDLU). I have no current involvement with that list, but I encourage folks to check it out!]
This section contains a short glossary and a list of helpful URLs.
The Coalition Against Unsolicited Commercial E-Mail. A volunteer organization that is trying to amend the United States junk fax law to apply to spam.
Classless Inter-Domain Routing; essentially a way for owners of Class B netblocks to partition them into smaller pieces and delegate them to customers.
When a spammer spamvertises the URL of a free website, rather than setting up a redirector, they will instead just place links to their site.
Domain Name System; how the Internet keeps track of which host name corresponds to which IP number (which is what the computers use internally).
Denial of Service. A type of attack against another system which cripples it. Examples include mail-bombing, ping flooding, and SYN flooding.
When a spammer creates an e-mail account on one system, then spams from another account, soliciting replies to the first e-mail account, or "dropbox". Free e-mail providers such as Yahoo and Hotmail are commonly used as dropboxes.
Excessive Multi-Posting (USENET term), aka Spam or Usenet Spam.
Harvesting, E-mail harvesting
The act of using a program (commonly known as a "spider" or "robot") to search either the web or Usenet and gather e-mail addresses. When spammers do this, they usually aren't able to filter out some of the munged addresses that are used which results in lots of bounces when the spam is sent out.
When spam is sent advertising a website run by an ISP which is a spam haven. See also: Spam Haven
A host that is relayed through.
Internet Service Provider. A company which sells Internet access to individuals or companies.
Local Area Network. An environment where a bunch of computers are hooked together so they can talk to each other, and the Internet if there is an Internet connection.
Imaginary piece of hardware using for hitting Whack-a-Mole spammers. :-)
news.admin.net-abuse.email; a USENET newsgroup which talks about e-mail spamming.
Nine Inch Nails [Had to, I just had to! ==Ed.]
Multi Level Marketing. A system where "sales reps" are really trying to recruit new salespeople instead of selling an actual product. Seen in a good number of spams. Read more about MLMs at http://www.falseprofits.com.
Make Money Fast, aka chain letters. Illegal in most civilized countries
Mail Delivery Agent. Delivers incoming e-mail. Examples include /bin/mail and procmail.
Mail Transport Agent. Commonly used on a UNIX system, where an e-mail program merely passes an outgoing message to the MTA, which usually runs 24/7 and handles getting the message to the other site. Examples include sendmail, qmail, smail, etc.
Mail User Agent. What you use to read and submit e-mail. Examples include Elm and Pine for UNIX systems, Eudora and MS Outlook for Windows systems.
Changing one's e-mail address so that it is invalid, but a human can determine the proper address. For example: email@example.com_NOSPAM. This technique is used to foil spammers who harvest addresses.
Having a spammer's account terminated.
A mailserver that permits relaying by anyone. Such systems are often abused by spammers and must be configured to prevent open relaying.
Requesting to be on a mailing list, a concept which the anti-spam community supports
Being added to a mailing list against your will, with the option of requesting to be removed. This is what spammers use for sending out their spams.
PGP (Pretty Good Privacy)
A popular encryption program which allows for users to send encrypted e-mail that only the recipient can read as well as allow a user to post a message that is "digitally signed" by them so that others can verify that the user actually sent that message. More information can be found on the International PGP Page at
A type of pyramid scheme where money from new "investors" (read: marks) is used to pay off older ones who think they made money. Eventually, too many people demand their money at once and the pyramid falls apart, resulting in chaos.
Post Office Protocol. A common protocol that is used for retrieving e-mail from a mailserver.
A scheme whereby a user must make a sucessful POP connection to a mailserver before being allowed to relay through it. This is very useful when a user wants to be able to send e-mail through their "home" ISP while they are connected to the net via another ISP.
A technique used by scammers whereby they create a ficticious company, drive up the value of its stock through phony claims and press releases, then selling off their shares of the stock at tremendous gains, scamming all the other people who bought stock. Pump-n-dump schemes are now taking place via spams.
The fundamental idea behind chain letters and MLM -- you know, send this to four of your friends and do not break the chain. A graphic model of this might look like a pyramid, where each new participator has to build their own "pyramid" of new participators in order for the scheme to work.
Realtime Blackhole List. A system maintained by Paul Vixie for blocking spam at the border router of your network. One nice thing about it is that once you "subscribe" to it, it is updated automatically so that you don't have to change something every time a new spammer starts up. More information can be found at http://mail-abuse.org/rbl/.
There has been a wave of spammers using free web sites. Rather than put their real data on the free site, they just put a page that includes the real site or automatically refreshes from the real page. So when the free web account gets nuked their real page is still there.
Passing your e-mail to a mailserver to deliver it on your behalf. This is abused by spammers when they find a third party system to relay thousands or millions of spams through.
When a spammer uses an open relay to send their spam.
An offer a spammer makes to put you on a special list so that you don't get any more spam from them. Signing up on a remove list is more than useless as spammers have been known to spam the addresses on them.
When a spammer forges a spam in another person's name with the intent of having that person deluged with hate mail or mailbombs, or losing their acccount with their ISP.
The reverse of a DNS lookup. That is, you enter an IP number, and you are told what name, if any, corresponds to it. If there is no name, you can always use whois or traceroute to determine who owns the system.
The most popular MTA for UNIX because it is very configurable. Until recently, there was no way for sendmail to prevent relaying which spammers usually take advantage of. More information on sendmail can be found at http://www.sendmail.org.
An ISP that allows spammers to maintain their website there as long as they do their spamvertising for it from somewhere else. See Also: Spamhaus
A site or ISP that doesn't terminate the e-mail or webhosting accounts of spammers. Often spammers will gravitate towards spamhauses as they don't have to worry about continually switching ISPs.
When a spammer creates an account on an ISP for the sole purpose of spamming, then proceeds to do so, knowing that it's only a matter of time, usually hours or days, until the account is cancelled.
A user who shows up in mailing lists and Usenet newsgroups who has nothing better to do but stir up arguments and flamewars between them and the users of that group. Most trolls just want the attention and will go away if they are ignored. SEE ALSO: Kook, Net.Scum, and Freedom Knights.
I used to have a link to netscum.org here, but that domain eventually expired and was bought by someone else. Please do not bother him. :-)
Unsolicited Bulk Email, aka spam.
Unsolicited Commercial Email, aka spam.
What spam is called when the spammer keeps jumping from ISP to ISP and is next to impossible to filter!
Term for an anti-spammer or an ISP that is anti-spam.
Spamhaus tracks the Internet's Spammers, Spam Gangs and Spam Services, provides dependable realtime anti-spam protection for Internet networks, and works with Law Enforcement to identify and pursue spammers worldwide.
RFC 1855, an official documement on proper netiquette which touches on the issue of net.abuse. However, it does go into sufficient detail for one to see that spammers are clearly violating it. This gives us more ammunition to use against spammers!
A list of responsible anti-spam sites which also contains e-mail addresses of the abuse departments for those sites as well as links to their (anti-spam) AUPs. (Disclaimer: I also maintain that page :-)
The Coalition Against Unsolicited E-Mail. CAUCE is a political advocacy group which is trying to fight spam on the legal front, as well as keep poorly written bills which would legitimize spam from passing.
This is a setup that systems "subscribe" to in order to receive a list of IP addresses and netblocks of sites that either spam or have open relaying being abused by spammers which are blocked automatically.
An e-mail service which allows you to create "disposable" e-mail addresses on their system. That way, if you give out such an address to a site that later spams you, you can delete that address and stop the flow of spam from them.