Safelist a Sender or Domain in SpamAssassin
Using its comprehensive set of rules and Bayesian analysis, SpamAssassin catches an impressive amount of spam with hardly any false positives — hardly any. To reduce this number even further, you can safelist certain newsletters, for instance, which tend to be top candidates for being erroneously classified as spam. While you’ll sometimes you’ll see the term safelist written as whitelist, the modern term is safelist. Some apps and code may still use the term whitelist. To safelist individual addresses or domains in SpamAssassin: The second parameter of whitelist_from_rcvd, a domain name which must be present in the Received header lines, is some prevention against spammers easily getting past SpamAssassin by using an email address at a commonly safelisted domain. To safelist only for yourself, open ~/.spamassassin/user_prefs.
What ‘AutoWhitelist’ Means and How It Works
SpamAssasin offers plug-ins that let you automate safelisting senders — not necessarily and not only in the manner you would assume, though. Both the older AWL (AutoWhitelist) and the improved TxRep plug-ins will monitor sending email addresses over time. Based on the reputation so built for addresses, the plug-ins will then adjust the spam score for an individual new message for each sender. If you received nothing but good mail from an address in the past, for example, just about anything they send now will be treated as good mail; even if they essentially forward a junk email, this message will pass through SpamAssassin unscathed with the help of AWL or TxRep. The sender will essentially be safelisted. Of course, that latest email will be factored into the sender’s reputation for the future, and repeated bad messages can modify it so that the sender is no longer “safelisted.” As a corollary, even the purest email from an address that has sent nothing but spam in the past will be treated as junk with AWL or TxRep enabled for SpamAssassin — with that good message slightly modifying the sender’s reputation for the future.
Use SpamAssassin TxRep to Safelist Addresses You Email
The TxRep SpamAssassin plug-in also includes the ability to watch the emails you send and automatically improve the reputation of each recipient address in each outgoing email, effectively safelisting people you email, and especially if you email them repeatedly. To have TxRep automatically improve the reputation of addresses you email: To safelist only for yourself, open ~/.spamassassin/user_prefs. Every time TxRep encounters an email address, it will add txrep_whitelist_out to the sender’s reputation score; the value increases over time as you email the same person repeatedly.
