MailScanner is a virus scanner for e-mail designed for use on e-mail gateways. It can also detect a large proportion of unsolicited commercial e-mail (spam) passing through it. Read more hot
SpamAssassin is a mail filter to identify spam using text analysis. Using its rule base, it uses a wide range of heuristic tests on mail headers and body text to identify "spam". SpamAssassin uses a wide variety of local and network tests to identify spam signatures. This makes it harder for spammers to identify one aspect which they can craft their messages to work around. Anti-spam tests and configuration are stored in plain text, making it easy to configure and add new rules. SpamAssassin encapsulates its logic in a well-designed, abstract API so it can be integrated anywhere in the email stream. The Mail::SpamAssassin classes can be used on a wide variety of email systems including procmail, sendmail, Postfix, qmail, and many others. Read more hot
Vipul's Razor is a distributed, collaborative, spam detection and filtering network. Through user contribution, Razor establishes a distributed and constantly updating catalogue of spam in propagation that is consulted by email clients to filter out known spam. Detection is done with statistical and randomized signatures that efficiently spot mutating spam content. User input is validated through reputation assignments based on consensus on report and revoke assertions which in turn is used for computing confidence values associated with individual signatures. Read more hot
Annoyance Filter sifts mail you wish to read from junk arriving in your mailbox by an adaptive process which gives priority to mail you're interested in reading.
AntiSpam Mail Filter
AntiSpam Mail Filter is a Bayesian filter to get rid of spam mails, designed for use with Exim.
Arbomb is an Archive "Bomb" detection utility which aims to increase the detection rate of melicious archive files that are capable of crippling non protected email filter servers.
Bayesian Mail Filter
Bayesian Mail Filter is a self contained and extremely efficient Bayesian mail filter. See Paul Graham's article "A Plan for Spam" for background information. It aims to be faster, smaller, and more versatile than similar applications.
bayespam is a spam filter for Qmail, although it should work with minor modification on many email servers.
Bogofilter is a mail filter that classifies mail as spam or ham (non-spam) by a statistical analysis of the message's header and content (body). The program is able to learn from the user's classifications and corrections.
Camram is a hybrid antispam system updating the physical-world concept of postage to the electronic age. Camram operates on a peer-to-peer basis using proof-of-work and digital signature techniques. The Camram system intentionally makes payment information visible, allowing intermediate machines to filter spam closer to its point of ingress to the global email system.
Chainmail Milter is a Sendmail mail filter (milter), which allows to manipulate emails passing through a Sendmail mail server in various ways. Based on the content of the email header and bodies, chainmail can add or remove recipients, reject messages, etc. Chainmail is intended to be a general purpose mail filter, comparable to the well-known procmail program in its mail filter mode.
Deep Six is a client side spam filtering tool that monitors your inbox for new email and filters it. The modular filter plugin-system allows for greater spam detection. It currently supports SpamBouncer, Vipul's Razor and DCC.
domadi [DO MAilDIr] is a daemon that monitors the contents of mail folders stored in maildir format. When changes are seen, actions can be taken. It can be used together with an IMAP server to automatically learn email that is moved into a junk folder as spam.
DSPAM is an open-source, freely available anti-spam project. DSPAM effectively filters spam system-wide using advanced techniques combined with one or more of the supported algorithms (Bayesian, Alternative Bayesian, and Chi-Square are currently supported). A majority of users achieve filtering rates ranging from 99.55% - 99.9%.
DynaStop is a utility to examine IPv4 based addresses for Exim and procmail for the purpose of filtering based upon patterns defined by the administrator. This can be a pivotal factor in email filtering and server load management, since dynamic IP addresses are typically used for dial-up, DHCP, and DSL accounts.
Evochallenge is a simple Perl-based challenge/response mail filter for Evolution on Linux.
Green Black List Creator for Procmail Recipes
Green Black List Creator for Procmail Recipes reads the .aliases file and orgs file then creates procmail recipes to filter your mail. Anytime a new alias is added or organization just re-run gb_list and the recipes will be updated.
ifile is a general purpose e-mail filter that has been adapted to a number of e-mail clients including MH, EXMH, Gnus, pine and procmail-compatible clients. It strives to be fast and efficient and to provide the best filtering possible. It can be used to filter out junk e-mail (aka spam).
IMAPFilter is a mail filtering utility. It connects to remote mail servers using the Internet Message Access Protocol (IMAP). Based on the user defined filters it checks messages residing on a remote IMAP mailbox and deletes unwanted emails accordingly.
Junk Mail Buffering Agent
Junk Mail Buffering Agent is a tool for preventing delivery of email until the sender has confirmed their address. It can be used in conjunction with a spam filter to prevent delivery of spammy-looking email unless the sender is confirmed as valid.
MailCleaner is a full email filtering gateway. It includes a complete GNU/Linux OS and a graphical web interface for user and administrative access. It comes in the form of an ISO image that contains a fully automated installer.
MailCorral is a robust, high-performance virus/spam filter program that runs as part of sendmail (using the milter interface) to filter out viruses and spam from all mail delivered on the site running sendmail.
(commercial) MailEnforcer delivers advanced Email Security functionality to organizations of all sizes that place a premium on flexibility and control.
Mailfilter is a flexible utility for UNIX (-like) operating systems to get rid of unwanted spam mails, before having to go through the trouble of downloading them into the local computer. It offers support for one or many POP3 accounts and is especially useful for dialup connections via modem, ISDN, etc.
(commercial) MailStripper is an SMTP spam filter with anti-virus capability, and is Mail Transfer Agent (MTA) independent.
MilterD is an anti-spam filter based upon the Sendmail Milter API. It is extremely effective when configured and is highly extensible.
Netfarm Mail Archiver
Netfarm Mail Archiver is a mail filter written in python, it parses all incoming/outcoming mails and extracts some fields. Then it passes these info to a zope server using xmlrpc and zope stores it into a dbms (tested with postgresql). The filter also backups mails on filesystem.
nodupmail is a procmail-based filtering system, designed to prevent or limit users from receiving duplicate mail messages. nodupmail is useful for those instances when you get get duplicate mails because a person mails both you and a list you are on. This is an often occurence in mailing lists where the Reply-To: field is not changed to be list, but users generally reply back to the list anyways, including the person they are replying directly too.
parp is a powerful, extensible, hackerware e-mail filter with sophisticated anti-spam capabilities. It's written in Perl.
PASP filters your email using a bayesian like statistical method. Written in 100% Python, easily extensible, and is used as a pop3 proxy to reduce the intrusion on your system.
PDFassassin is a module for SpamAssassin that allows for the scanning of PDF files in email message attachments. Email bodies are scanned upon connection and checked for PDF attachments. Text is extracted from the PDF via pdftotext and scanned by SpamAssassin. Should the PDF contain images, the gocr program is called to extract the text content. The total spam score of the PDF is compared against the global required_score setting; if it's higher, a score equal to the one specified in pdf.cf is appended to the overall score of the email message.
PMilter is an attempt to reimplement Sendmail's milter (mail filter) protocol in pure Perl. There are many reasons for this, including independence from Sendmail's libmilter, as well as freedom from POSIX threads (helps stability for Perl filters), etc.
Popsneaker is a mailfilter for remote filtering of POP3 email accounts. It is useful for computers which have a dial-in connection to the internet. You can define rules to select emails, which you don't want to download to your local host.
Pydspam is a Python wrapper for the dspam project. It provides full access to the features of libdspam, and a high level API to handle message tagging and signature database
qmail-rblchk filters all incoming mail and check if it comes from RBL listed IPs.
Quick Spam Filter
Quick Spam Filter is a lightweight Bayesian-like spam filter written in C using the commonly used GDBM library to store its token database. It is designed to be small, fast, reliable, easy to install, and simple to use in a procmail recipe.
RBL Spam Daemon
A SpamAssassin-compatible spam filter that uses only DNS Blocking Lists to distinguish spam from regular mail. As a result, it is highly accurate, small, and fast. The server process uses less memory than a shell, and takes very little CPU time.
RubyFilter is a Ruby email filtering program that can serve as a replacement for email delivery programs such as procmail. It is also a Ruby module which provides classes that make it easy to write programs that filter and deliver email.
Scam-grey is a milter which filters mail originating from MS Windows hosts. It provides you the ability to mitigate the flow of unwanted email from such hosts using grey listing.
Scam-protect is a milter which restricts the use of your domain address in emails. Its aim is to protect your users from phishing by rejecting mail purporting to be from your domain.
scmail is a mail filter written in Scheme. scmail can filter an incoming mail when it is received and filter mails in a mailbox. A bayesian spam filter called scbayes is also included.
Sendmail Confirmation System
SMC (SendMail Control system) - is an software application designed to significantly reduce the amount of SPAM/UCE (junk-mail) you receive. SMC uses a dynamic local and DNS based remote "whitelists" (for known/trusted senders), DNS based "blacklists" (for undesired senders), and an original "autoauthentication" system (for unknown, but legitimate senders).
GreyList Sendmail milter is a lightweight, fast, and reliable Sendmail milter that implements the Greylisting antispam technology. It has a flexible configuration and a very effective Greylisting algorithm on the base of this tuple: sender's IP address (Class C subnet), envelope sender address, and envelope recipient address. It's a light alternative to the milter-greylist, graymilter, and milter-gris milters.
Spam Trainer makes it easier for GNOME users to train spam filtering software (e.g. SpamBayes or SpamAssassin) that "learns" how to tell the difference between real email (ham) and unsolicited messages.
SpamBayes is a Bayesian anti-spam classifier written in Python. Read more
SpamDam gets rid of spam using disposable e-mail addresses! Disable compromised addresses, or auto-reply with a web form allowing actual humans to get through. SpamDam rewrites all emails to include the actual "To" address so you can easily filter.
spamdyke is a drop-in filter for qmail to provide connection-time blacklisting, graylisting, DNS RBL checking, improved logging, and more. spamdyke does not require patching or recompiling qmail.
SpamFilters is a collection of rulesets that expand on sendmail's anti-spam facilities. It integrates into sendmail by way of the distribution's m4 build hierarchy, but can be added directly to sendmail's configuration file if need be.
SpamFirewall is a mail server filter script that automatically blocks mail servers that send too much spam.
Spammilt is a sendmail-milter which scans the header of emails for blacklistes-relaying servers and locally predefined blacklisted domains/words. By default when spammilt detects *spam*, spammilt adds a warning to the header and the subject, as an option it's also possible to rejects such emails without bothering the recipient.