Bogofilter is a trainable email spam detector.
Bogofilter takes an email message or other text on standard input, parses it
into words, does a statistical check against databases of "good" and "bad"
words, and returns a status code indicating whether or not the message is spam.
Bogofilter decodes base64 or quoted-printable encoded texts and ignores non-text
attachments and HTML comments.
The supported database backends are Berkeley DB, QDBM and SQLite3.
spamdyke is a filter for monitoring and intercepting SMTP
connections between a remote host and a qmail server. Spam
is blocked while the remote server (spammer) is still
connected; no additional processing or storage is needed.
In addition to all of its anti-spam filters, spamdyke also
includes a number of features to enhance qmail.
Best of all, using spamdyke does not require patching or
The dovecot antispam plugin is aimed to help in spam systems training.
Consider the following scenario. Your mailbox is flooded with tons of
mail. They are delivered to the configured folders based on the
arbitrary spam system judgement. This judgement is not always correct
or not always what you would like it to be, however. This is where
this plugin comes into play.
All you have to do is move the mail into the correct folder. All the
rest in order to let the spam system know it made an error will be
done automatically by this plugin.
It watches for when you move the mail to some folder and acts
accordingly. The advantage of this approach is that the mail ends up
in the right target folder directly and needs not be touched twice.
The skem utility is a sendmail milter, that checks and maintains a list
of whitelisted, temporary banned, and permanently blacklisted
IP-addresses. How you obtain the entries is up to you, but the included
logwatcher module provides one possibility.
The list is stored in a directory, each entry being a file (usually --
zero sized) or a symlink (usually -- a "broken" one). Such entries are
stored efficiently (within the directory itself) and the directories are
searched using the hash tables on modern file systems. At the same time,
they can be listed, added, and removed with the simple ls(1), touch(1),
This milter does not itself filter spam, instead it memorizes the
verdicts issued by your other anti-spam defenses to reduce the system
load and resource consumption, by temporarily rejecting the relays
suspected of spamming (banned) and, optionally, by permanently rejecting
the relays "convicted" of spamming (blacklisted).
The idea is to stem the spam from real spam sources, while reducing the
ill effects of false-positives to merely delaying, rather than rejecting
Policyd is an anti-spam plugin for Postfix (written in C) that does :
o Sender-(envelope, SASL or host / ip)-based throttling
(on messages and/or volume per defined time unit),
o Recipient rate limiting,
o Spamtrap monitoring / blacklisting,
o HELO auto blacklisting
o HELO randomization preventation,
o Sender mail addresses or domain Sender blacklisting
Pyzor is a collaborative, networked system to detect and block spam using
identifying digests of messages.
Pyzor initially started out to be merely a Python implementation of Razor,
but due to the protocol and the fact that Razor's server is not Free Software,
I decided to Pyzor should be based upon a new, lighter, more language-
Nearly all of today's mail system administrators face spam as their
first threat. Because of this, EnderUNIX team has written this small
application to automagically monitor malicious spammer activity in
your mail server logs.
spamGuard is written purely in C, to stop spammers hanging around.
The program supports nearly all mostly used MTAs; qmail (both
multilog and splogger), sendmail and Postfix.
Roundcube plugin to manage SpamAssassin preferences.
Adds a 'Spam' tab to the 'Personal Settings' to allow the user to change
their SpamAssassin preferences. Preferences must be stored in a SQL
database. Default preferences are used when no user preference is found.
Simscan is a simple program that enables qmail-smtpd to reject
viruses, spam and block attachments during the SMTP conversation
so the email never makes it into your computers. It is completely
open source and uses other open source components.
Very efficient and written in C.
A script that generates statistics about spam you receive at your site.
The script parses maillog file, generated by exim/postfix/sendmail and spamd.
The script will currently not work with other mailers than exim, postfix or
sendmail (contributions will be welcome) or if you do not use spamd.