On 23/10/2010 5:47 PM, RW wrote:
On Sat, 23 Oct 2010 14:28:38 -0230
"Lawrence @ Rogers"<lawrencewilli...@nl.rogers.com>  wrote:

Hello all,

I noticed recently that our users are getting spam with the subject
similar to the following:

SehxpyNaturalRedheaddFayeReaganHasHerFirstLesbianExperienceWithBrunet

I got some of these a while ago. They were pretty hard to catch because
they came through Hotmail and had little to work with in the body.
I added:


header    SUBJ_LONG_WORD               Subject  =~ /\b[^[:space:][:punct:]]{30}/
describe  SUBJ_LONG_WORD               Longwordinsubjectlikethis
score     SUBJ_LONG_WORD               2.0

header    SUBJ_JOIN_CAP_WORD           Subject  =~ 
/([[:upper:]]+[[:lower:]]+){5}/
describe  SUBJ_JOIN_CAP_WORD           JoinedCapitalizedWordsRuntogether
score     SUBJ_JOIN_CAP_WORD           1.5


They are missing some "?:", but for single header rules I don't really
care.

Thanks, but some testing showed that your rules FP on URLs in the Subject line.

I have settled on the following as it's more specific and less prone to FPs (I can't think of any possibilities right now)

# Matches a new technique used by spammers in the Subject line
# Running a bunch of pornographic words together (with no spaces) to evade spam filters # The message itself is generally malformed HTML with one or more unusually long lines # This rule is a meta rule that tests for the Subject containing any numbers, letters, or common formatting # Must hit at least 3 SA rules (__LOCAL_SUBJECT_SPAMMY, and 2 others... usually HTML_MESSAGE and MIME_QP_LONG_LINE)
# string must be at least 42 characters and contain no spaces

header __LOCAL_SUBJECT_SPAMMY  Subject =~ /^[0-9a-zA-Z,.+]{42,}$/
meta LOCAL_SUBJECT_SPAMMY1 ((__LOCAL_SUBJECT_SPAMMY + HTML_MESSAGE + MIME_QP_LONG_LINE + MPART_ALT_DIFF + TRACKER_ID) > 2) describe LOCAL_SUBJECT_SPAMMY1 Subject looks spammy (contains a lot of characters, and no spaces)
score  LOCAL_SUBJECT_SPAMMY1 5.0
tflags LOCAL_SUBJECT_SPAMMY1 noautolearn

Cheers,
Lawrence Williams
LCWSoft

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