I am using sendmail.

> On Dec 2, 2017, at 12:33 PM, David Jones <[email protected]> wrote:
> 
>> On 12/02/2017 10:39 AM, Junk wrote:
>> i implemented all of the filters yo mentioned and the score went up from 
>> 3.5. to 3.9 on an example spam email i was testing.
>> I will look further into more filters.
>> I see lots of spam that is formatted as image and those are not being caught.
> 
> What is your MTA?  If you are using Postfix then definitely enable postscreen 
> plus it's weighted RBLs.  Then you can combine the power of multiple RBLs 
> that would normally be too risky to reject on their own to make them more 
> reliable.
> 
> Then you can start experimenting with RBLs at 
> http://multirbl.valli.org/lookup/ with low weights and slowly bump them up as 
> you find ones that are helpful for your particular mail flow. Here is my 
> current list:
> 
> postscreen_dnsbl_sites =
>  dnsbl.sorbs.net=127.0.0.[10;14]*9
>  zen.spamhaus.org=127.0.0.[10;11]*8
>  dnsbl.sorbs.net=127.0.0.5*7
>  zen.spamhaus.org=127.0.0.[4..7]*7
>  b.barracudacentral.org=127.0.0.2*7
>  zen.spamhaus.org=127.0.0.3*7
>  dnsbl.inps.de=127.0.0.2*7
>  hostkarma.junkemailfilter.com=127.0.0.2*4
>  dnsbl.sorbs.net=127.0.0.7*4
>  bl.spamcop.net=127.0.0.2*4
>  bl.spameatingmonkey.net=127.0.0.[2;3]*4
>  dnsrbl.swinog.ch=127.0.0.3*4
>  ix.dnsbl.manitu.net=127.0.0.2*4
>  psbl.surriel.com=127.0.0.2*4
>  bl.mailspike.net=127.0.0.[10;11;12]*4
>  bl.mailspike.net=127.0.0.2*4
>  ubl.unsubscore.com=127.0.0.2*4
>  zen.spamhaus.org=127.0.0.2*3
>  dnsbl-1.uceprotect.net=127.0.0.2*2
>  dnsbl.sorbs.net=127.0.0.6*3
>  dnsbl.sorbs.net=127.0.0.9*2
>  dnsbl.sorbs.net=127.0.0.8*2
>  score.senderscore.com=127.0.4.[0..29]*2
>  hostkarma.junkemailfilter.com=127.0.0.4*2
>  all.spamrats.com=127.0.0.38*2
>  bl.nszones.com=127.0.0.[2;3]*1
>  dnsbl-2.uceprotect.net=127.0.0.2*1
>  dnsbl.sorbs.net=127.0.0.2*1
>  dnsbl.sorbs.net=127.0.0.4*1
>  score.senderscore.com=127.0.4.[30..69]*1
>  all.spamrats.com=127.0.0.38*2
>  bl.nszones.com=127.0.0.[2;3]*1
>  dnsbl-2.uceprotect.net=127.0.0.2*1
>  dnsbl.sorbs.net=127.0.0.2*1
>  dnsbl.sorbs.net=127.0.0.4*1
>  score.senderscore.com=127.0.4.[30..69]*1
>  dnsbl.sorbs.net=127.0.0.3*1
>  hostkarma.junkemailfilter.com=127.0.1.2*1
>  dnsbl.sorbs.net=127.0.0.15*1
>  ips.backscatterer.org=127.0.0.2*1
>  bl.nszones.com=127.0.0.5*-1
>  wl.mailspike.net=127.0.0.[18;19;20]*-2
>  hostkarma.junkemailfilter.com=127.0.0.1*-2
>  ips.whitelisted.org=127.0.0.2*-2
>  safe.dnsbl.sorbs.net=127.0.[0..255].0*-2
>  list.dnswl.org=127.0.[0..255].0*-2
>  dnswl.inps.de=127.0.[0;1].[2..10]*-2
>  list.dnswl.org=127.0.[0..255].1*-3
>  list.dnswl.org=127.0.[0..255].2*-4
>  list.dnswl.org=127.0.[0..255].3*-5
> 
> - Setup postwhite with Postfix to bypass major/trusted senders so you don't 
> reject too much with the above RBL lists.
> 
> - Enable basic DNS check in Postfix main.cf:
> 
> smtpd_recipient_restrictions =
>  permit_mynetworks,
>  ...,
>  permit_sasl_authenticated,
>  reject_non_fqdn_sender,
>  reject_non_fqdn_recipient,
>  reject_non_fqdn_hostname,
>  reject_invalid_hostname,
>  reject_unauth_destination,
>  reject_unverified_recipient,
>  reject_unknown_reverse_client_hostname,
>  reject_unknown_sender_domain,
>  reject_unlisted_sender,
>  reject_unlisted_recipient,
>  ...,
> 
> 
> - Enable greylisting if you can.  It really does work, especially helpful 
> with zero-hour spammers from compromised accounts that are very difficult to 
> block.  It is possible to deploy it slowly so users don't notice a delay.
> 
> - Enable Postfix rate limiting.
> 
> - Install pypolicyd-spf, OpenDKIM, OpenDMARC to add headers that SA can use.  
> OpenDMARC with some custom rules can give Spamassassin basic DMARC support.
> 
> header        DMARC_PASS    Authentication-Results =~ /your-server-here; 
> dmarc=pass/
> describe    DMARC_PASS    DMARC check passed
> score        DMARC_PASS    -0.01
> 
> header        DMARC_FAIL    Authentication-Results =~ /your-server-here; 
> dmarc=fail/
> describe    DMARC_FAIL    DMARC check failed
> score        DMARC_FAIL    0.01
> 
> header        DMARC_NONE    Authentication-Results =~ /your-server-here; 
> dmarc=none/
> describe    DMARC_NONE    DMARC check neutral
> score        DMARC_NONE    0.01
> 
> header        DMARC_FAIL_REJECT    Authentication-Results =~ 
> /your-server-here; dmarc=fail \(p=reject/
> describe    DMARC_FAIL_REJECT    DMARC check failed and the sending domains 
> says to reject this message
> score        DMARC_FAIL_REJECT    8.2
> 
> 
> - Consider slightly bumping up the scores on FREEMAIL* rules this these are 
> often sources of abuse.
> 
> - Add DecodeShortURLs.pm and DecodeShortURLs.cf
> 
> - Enable Lashback RBL in SA /etc/mail/spamassassin/lashback.cf:
> 
> ifplugin Mail::SpamAssassin::Plugin::DNSEval
> 
> header        __RCVD_IN_LASHBACK    eval:check_rbl('lashback', 
> 'ubl.unsubscore.com.')
> describe    __RCVD_IN_LASHBACK    Received is listed in Lashback 
> ubl.unsubscore.com
> tflags        __RCVD_IN_LASHBACK    net
> 
> header        RCVD_IN_LASHBACK    eval:check_rbl_sub('lashback', '127.0.0.2')
> describe    RCVD_IN_LASHBACK    Received is listed in Lashback 
> ubl.unsubscore.com
> score        RCVD_IN_LASHBACK    1.2
> tflags        RCVD_IN_LASHBACK    net
> 
> header        RCVD_IN_LASHBACK_LASTEXT    
> eval:check_rbl('lashback-lastexternal', 'ubl.unsubscore.com.')
> describe    RCVD_IN_LASHBACK_LASTEXT    Last external is listed in Lashback 
> ubl.unsubscore.com
> score        RCVD_IN_LASHBACK_LASTEXT    2.2
> tflags        RCVD_IN_LASHBACK_LASTEXT    net
> 
> endif
> 
> - Make sure that DCC, Razor, and Pyzor are installed and there are hits in 
> your mail logs.
> 
> - Properly train your Bayesian DB with spam first then ham second.
> 
> - Have a huge list of whitelist_auth and whitelist_from_rcvd entries for 
> trusted senders which allows me to bump up many scores without causing false 
> positives on them.
> 
>>> On Dec 1, 2017, at 5:05 PM, Kevin Miller <[email protected]> wrote:
>>> 
>>> There's a number of rulesets that I use - many are mentioned here in this 
>>> list and discussed so a look at the archives will probably be helpful.
>>> 
>>> KAM - http://www.pccc.com/downloads/SpamAssassin/contrib/KAM.cf
>>> Hashcash
>>> HashBL
>>> SEM - spameatingmonkey.net
>>> 
>>> To mention just a few...
>>> 
>>> 
>>> ...Kevin
>>> --
>>> Kevin Miller
>>> Network/email Administrator, CBJ MIS Dept.
>>> 155 South Seward Street
>>> Juneau, Alaska 99801
>>> Phone: (907) 586-0242, Fax: (907) 586-4588 Registered Linux User No: 307357
>>> 
>>> 
>>> -----Original Message-----
>>> From: Junk [mailto:[email protected]]
>>> Sent: Friday, December 01, 2017 1:36 PM
>>> To: Kevin Miller
>>> Cc: [email protected]
>>> Subject: RE: FIlter
>>> 
>>> Do  you know any additional lists that could be added in addition to:
>>> - built ones
>>> - http://wiki.junkemailfilter.com
>>> - razors
>>> 
>>> I have the spam score set to above to be 100% spam as i noticed what is 
>>> below 5% sometimes falls into not a spam email.
>>> 
> 
> -- 
> David Jones

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