Disabling a shipped rule in SpamAssassin

2007-08-10 Thread Kelly Jones
How do I disable a rule in /usr/local/share/spamassassin/*.cf? I'm tempted to comment it out, but the headers say to not do that. If I put something in /etc/mail/spamassassin/local.cfg, I can override the definition of an existing rule (right?), but that doesn't let me delete a rule. If I wanted

List of frequently spoofed domains/addresses?

2009-05-10 Thread Kelly Jones
When one of our customers emails someone, we whitelist the recipient address so that the return email won't be blocked [1]. Some users foolishly whitelist ad...@paypal.com, so that phishing emails go right through. Where can I find a list of "frequently spoofed addresses" (or domains)? We can th

Trusting TLS for spamfighting purposes?

2008-10-06 Thread Kelly Jones
Can SpamAssassin negative score emails that are sent using TLS? I realize anyone (even spammers) can use TLS, but I tend to trust encrypting mail servers more than I do non-encrypting ones. However, I'm guessing all evidence of TLS usage has disappeared by the time SpamAssassin gets the message?

Bad check_for_from_to_same code in EvalTests.pm?

2008-12-03 Thread Kelly Jones
SA doesn't use EvalTests.pm's check_for_from_to_same test, but part of the code looks like this: return 0 if (!length($hdr_from) || !length($hdr_to) || $hdr_from eq $hdr_to); Is that right? Shouldn't the 'eq' be 'ne'? -- We're just a Bunch Of Regular Guys, a collective group th

Running message through a single SA test

2008-12-03 Thread Kelly Jones
I want to run a message through ONE SpamAssassin test w/o the overhead of running all the tests. I realize many SA tests are just regexs (so I could use procmail or something), but this test is a meta test and it may change from time to time. Does SA have a "--run-just-this-test=FOO" option? --

List of fake email addresses spammers use?

2006-11-23 Thread Kelly Jones
Spammers often spoof fake email addresses when sending email, eg "[EMAIL PROTECTED]". It's easy to tell this address is fake: host -t mx lycos.com lycos.com mail is handled by 10 rmail-alt2.lycosmail.lycos.com. lycos.com mail is handled by 5 rmail.lycosmail.lycos.com. lycos.com mail is handled

Percentage of email that is spam after filtering?

2006-11-24 Thread Kelly Jones
I know that most (90%+) email sent now is spam, but what are the numbers for people who use spam filtering? I realize it varies by user, sensitivity to false positives, tools used, etc, but do people who use spam filtering find that only 10% of the messages they receive are spam? 25%? 50%? higher

Re: Percentage of email that is spam after filtering?

2006-11-25 Thread Kelly Jones
Thanks to everyone who is replying here. Additional replies/comments always appreciated. What started me thinking about this is this non-intuitive but mathematically valid "paradox" that Bookworm and others have noticed: If 95% of all email is spam, and I correctly tell users that I block 95% of

Spamassassin doesn't ding sender for saying "HELO i-am-you"

2006-12-06 Thread Kelly Jones
Spamassassin has lots of tests for fake HELOs. If someone says "HELO hotmail.com", but aren't connecting from a Hotmail IP address, they get dinged (spam score is increased). Recently, someone connected our server, call it mx.xyz.com, and said "HELO mx.xyz.com". Spamassassin didn't ding it for do

FuzzyOCR hashdb tagging commonly-used images like spacer.gif as spam

2006-12-17 Thread Kelly Jones
We turned on FuzzyOCR's experimental "hashdb" function, but had to turn it off again after it tagged the following images (hashes) as spam: 8:1:1:1::1:1:1:1:1 14:1:1:1::0:0:0:0:1 These appear to be "spacer.gif"-like images: small images commonly used in HTML messages for formatting purposes. Ha

Rule that negative scores emails from blackberry.com, not spoofers

2006-12-18 Thread Kelly Jones
How do I write a rule that negative scores emails "from" blackberry.com. In other words, where the reverse DNS of the IP address connecting to my mailserver matches the regex /.*blackberry\.com$/ The obvious: Received =~ /.*blackberry\.com$/ doesn't work, because someone could "HELO blackberry.

Capturing regular expression while testing new rule?

2006-12-21 Thread Kelly Jones
Many people write test rules w/ small negative scores like this: header SUBJ_FOO_BAR_TEST Subject =~ /foo.*bar/ describe SUBJ_FOO_BAR_TEST Subject contains both "foo" and "bar" in that order score SUBJ_FOO_BAR_TEST -0.001 The logs will then show when SUBJ_FOO_BAR_TEST is hit. I want to go one s

Despeckling images for OCR and anti-spam purposes

2006-12-22 Thread Kelly Jones
Spammers are starting to put "speckles" in their images to defeat OCR-scanning plugins such as FuzzyOCR. I thought ImageMagick's -despeckle option would help, but it doesn't seem to, not even when applied multiple times, not even in conjunction with -monochrome. I want a filter that does this fo

Which is more efficient: two regexp's or one regexp with alternation?

2007-01-16 Thread Kelly Jones
If I want to block subjects matching "foo" or "bar", is it more efficient to write two regexps or a single "foo|bar" regexp? I'd think a single regexp is more efficient, but SpamAssassin ships w/ rule-sets that have multiple rules. Given how many spams people get, even a small improvement in effi

Blacklisting efficiently using "first and final" rules?

2007-01-17 Thread Kelly Jones
Blacklisting with SpamAssassin is easy: just add a rule with a high score. However, this seems inefficient, since SpamAssassin will still go through its entire ruleset to calculate a score. Is it possible to setup "first and final" rules in SpamAssassin. That is, rules that are: 1) checked befor

Finding when a certain rule became part of SpamAssassin distribution

2007-02-02 Thread Kelly Jones
I'd like to find out when the (meta) rule RATWARE_OUTLOOK_NONAME was added to SpamAssassin (which version first included it as part of the standard distribution?). This rule isn't listed at "http://spamassassin.apache.org/tests_3_1_x.html"; (possibly because that page doesn't include meta rules?)

Submitting RBL blocks to SORBS + how to identify ADSL/etc blocks

2007-03-08 Thread Kelly Jones
I recently (~26 Feb 2007) submitted two RBL blocks to SORBS (85.93.37.128-85.93.37.191 and 86.212.217.0-86.212.217.255). My emails created 2 tickets on rt.sorbs.net, but the tickets remain "new", even though the autoreply said they should be handled in 24-48 hours. The tickets did get moved from t

Tool for validating sender address as spam-fighting technique?

2007-03-10 Thread Kelly Jones
To fight spam, I want to validate the address (not necessarily in real-time) of the a given email sender. Is there a Unix tool that does this? The basics are simple: to validate "[EMAIL PROTECTED]", I connect to the MX record of wnonline.net and go as far as "RCPT TO" as follows: host -t mx wno

Email service that does graylisting/razor/spamfiltering/etc?

2007-04-09 Thread Kelly Jones
I have about 20 domains, and any email to any of these domains ([EMAIL PROTECTED]) forwards to a single mailbox. I handle email for all these domains myself, but it's becoming a hassle: % dictionary attacks mean I often get the same spam repeatedly % I'm too scared to change my SMTP config (to