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Meph
7th July 2009, 16:21
I am using Ubuntu Server 9.04 and used the Perfect Server ISPConfig 3 howto for my distribution.

I have been searching far and wide for answers to my spam problems, most of the answers I have found here in this forum. Here is /etc/amavis/conf.d/20-debian_defaults:

use strict;

# ADMINISTRATORS:
# Debian suggests that any changes you need to do that should never
# be "updated" by the Debian package should be made in another file,
# overriding the settings in this file.
#
# The package will *not* overwrite your settings, but by keeping
# them separate, you will make the task of merging changes on these
# configuration files much simpler...

# see /usr/share/doc/amavisd-new/examples/amavisd.conf-default for
# a list of all variables with their defaults;
# see /usr/share/doc/amavisd-new/examples/amavisd.conf-sample for
# a traditional-style commented file
# [note: the above files were not converted to Debian settings!]
#
# for more details see documentation in /usr/share/doc/amavisd-new
# and at http://www.ijs.si/software/amavisd/amavisd-new-docs.html

$QUARANTINEDIR = "$MYHOME/virusmails";
$quarantine_subdir_levels = 1; # enable quarantine dir hashing

$log_recip_templ = undef; # disable by-recipient level-0 log entries
$DO_SYSLOG = 1; # log via syslogd (preferred)
$syslog_ident = 'amavis'; # syslog ident tag, prepended to all messages
$syslog_facility = 'mail';
$syslog_priority = 'debug'; # switch to info to drop debug output, etc

$enable_db = 1; # enable use of BerkeleyDB/libdb (SNMP and nanny)
$enable_global_cache = 1; # enable use of libdb-based cache if $enable_db=1

$inet_socket_port = 10024; # default listening socket

$sa_spam_subject_tag = '***SPAM*** ';
$sa_tag_level_deflt = 2.0; # add spam info headers if at, or above that level
$sa_tag2_level_deflt = 6.31; # add 'spam detected' headers at that level
$sa_kill_level_deflt = 6.31; # triggers spam evasive actions
$sa_dsn_cutoff_level = 10; # spam level beyond which a DSN is not sent

$sa_mail_body_size_limit = 200*1024; # don't waste time on SA if mail is larger
$sa_local_tests_only = 0; # only tests which do not require internet access?

# Quota limits to avoid bombs (like 42.zip)

$MAXLEVELS = 14;
$MAXFILES = 1500;
$MIN_EXPANSION_QUOTA = 100*1024; # bytes
$MAX_EXPANSION_QUOTA = 300*1024*1024; # bytes

# You should:
# Use D_DISCARD to discard data (viruses)
# Use D_BOUNCE to generate local bounces by amavisd-new
# Use D_REJECT to generate local or remote bounces by the calling MTA
# Use D_PASS to deliver the message
#
# Whatever you do, *NEVER* use D_REJECT if you have other MTAs *forwarding*
# mail to your account. Use D_BOUNCE instead, otherwise you are delegating
# the bounce work to your friendly forwarders, which might not like it at all.
#
# On dual-MTA setups, one can often D_REJECT, as this just makes your own
# MTA generate the bounce message. Test it first.
#
# Bouncing viruses is stupid, always discard them after you are sure the AV
# is working correctly. Bouncing real SPAM is also useless, if you cannot
# D_REJECT it (and don't D_REJECT mail coming from your forwarders!).

$final_virus_destiny = D_DISCARD; # (data not lost, see virus quarantine)
$final_banned_destiny = D_BOUNCE; # D_REJECT when front-end MTA
$final_spam_destiny = D_DISCARD;
$final_bad_header_destiny = D_DISCARD; # False-positive prone (for spam)

$virus_admin = "postmaster\@$mydomain"; # due to D_DISCARD default

# Set to empty ("") to add no header
$X_HEADER_LINE = "Debian $myproduct_name at $mydomain";

# REMAINING IMPORTANT VARIABLES ARE LISTED HERE BECAUSE OF LONGER ASSIGNMENTS

#
# DO NOT SEND VIRUS NOTIFICATIONS TO OUTSIDE OF YOUR DOMAIN. EVER.
#
# These days, almost all viruses fake the envelope sender and mail headers.
# Therefore, "virus notifications" became nothing but undesired, aggravating
# SPAM. This holds true even inside one's domain. We disable them all by
# default, except for the EICAR test pattern.
#

@viruses_that_fake_sender_maps = (new_RE(
[qr'\bEICAR\b'i => 0], # av test pattern name
[qr/.*/ => 1], # true for everything else
));

@keep_decoded_original_maps = (new_RE(
# qr'^MAIL$', # retain full original message for virus checking (can be slow)
qr'^MAIL-UNDECIPHERABLE$', # recheck full mail if it contains undecipherables
qr'^(ASCII(?! cpio)|text|uuencoded|xxencoded|binhex)'i,
# qr'^Zip archive data', # don't trust Archive::Zip
));


# for $banned_namepath_re, a new-style of banned table, see amavisd.conf-sample

$banned_filename_re = new_RE(
# qr'^UNDECIPHERABLE$', # is or contains any undecipherable components

# block certain double extensions anywhere in the base name
qr'\.[^./]*\.(exe|vbs|pif|scr|bat|cmd|com|cpl|dll)\.?$'i,

qr'\{[0-9a-f]{8}(-[0-9a-f]{4}){3}-[0-9a-f]{12}\}?$'i, # Windows Class ID CLSID, strict

qr'^application/x-msdownload$'i, # block these MIME types
qr'^application/x-msdos-program$'i,
qr'^application/hta$'i,

# qr'^application/x-msmetafile$'i, # Windows Metafile MIME type
# qr'^\.wmf$', # Windows Metafile file(1) type

# qr'^message/partial$'i, qr'^message/external-body$'i, # rfc2046 MIME types

# [ qr'^\.(Z|gz|bz2)$' => 0 ], # allow any in Unix-compressed
# [ qr'^\.(rpm|cpio|tar)$' => 0 ], # allow any in Unix-type archives
# [ qr'^\.(zip|rar|arc|arj|zoo)$'=> 0 ], # allow any within such archives
# [ qr'^application/x-zip-compressed$'i => 0], # allow any within such archives

qr'.\.(exe|vbs|pif|scr|bat|cmd|com|cpl)$'i, # banned extension - basic
# qr'.\.(ade|adp|app|bas|bat|chm|cmd|com|cpl|crt|emf |exe|fxp|grp|hlp|hta|
# inf|ins|isp|js|jse|lnk|mda|mdb|mde|mdw|mdt|mdz|msc |msi|msp|mst|
# ops|pcd|pif|prg|reg|scr|sct|shb|shs|vb|vbe|vbs|
# wmf|wsc|wsf|wsh)$'ix, # banned ext - long

# qr'.\.(mim|b64|bhx|hqx|xxe|uu|uue)$'i, # banned extension - WinZip vulnerab.

qr'^\.(exe-ms)$', # banned file(1) types
# qr'^\.(exe|lha|tnef|cab|dll)$', # banned file(1) types
);
# See http://support.microsoft.com/default.aspx?scid=kb;EN-US;q262631
# and http://www.cknow.com/vtutor/vtextensions.htm


# ENVELOPE SENDER SOFT-WHITELISTING / SOFT-BLACKLISTING

@score_sender_maps = ({ # a by-recipient hash lookup table,
# results from all matching recipient tables are summed

# ## per-recipient personal tables (NOTE: positive: black, negative: white)
# 'user1@example.com' => [{'bla-mobile.press@example.com' => 10.0}],
# 'user3@example.com' => [{'.ebay.com' => -3.0}],
# 'user4@example.com' => [{'cleargreen@cleargreen.com' => -7.0,
# '.cleargreen.com' => -5.0}],

## site-wide opinions about senders (the '.' matches any recipient)
'.' => [ # the _first_ matching sender determines the score boost

new_RE( # regexp-type lookup table, just happens to be all soft-blacklist
[qr'^(bulkmail|offers|cheapbenefits|earnmoney|foryo u)@'i => 5.0],
[qr'^(greatcasino|investments|lose_weight_today|mar ket\.alert)@'i=> 5.0],
[qr'^(money2you|MyGreenCard|new\.tld\.registry|opt-out|opt-in)@'i=> 5.0],
[qr'^(optin|saveonlsmoking2002k|specialoffer|specia loffers)@'i => 5.0],
[qr'^(stockalert|stopsnoring|wantsome|workathome|ye sitsfree)@'i => 5.0],
[qr'^(your_friend|greatoffers)@'i => 5.0],
[qr'^(inkjetplanet|marketopt|MakeMoney)\d*@'i => 5.0],
),

# read_hash("/var/amavis/sender_scores_sitewide"),

{ # a hash-type lookup table (associative array)
'nobody@cert.org' => -3.0,
'cert-advisory@us-cert.gov' => -3.0,
'owner-alert@iss.net' => -3.0,
'slashdot@slashdot.org' => -3.0,
'securityfocus.com' => -3.0,
'ntbugtraq@listserv.ntbugtraq.com' => -3.0,
'security-alerts@linuxsecurity.com' => -3.0,
'mailman-announce-admin@python.org' => -3.0,
'amavis-user-admin@lists.sourceforge.net'=> -3.0,
'amavis-user-bounces@lists.sourceforge.net' => -3.0,
'spamassassin.apache.org' => -3.0,
'notification-return@lists.sophos.com' => -3.0,
'owner-postfix-users@postfix.org' => -3.0,
'owner-postfix-announce@postfix.org' => -3.0,
'owner-sendmail-announce@lists.sendmail.org' => -3.0,
'sendmail-announce-request@lists.sendmail.org' => -3.0,
'donotreply@sendmail.org' => -3.0,
'ca+envelope@sendmail.org' => -3.0,
'noreply@freshmeat.net' => -3.0,
'owner-technews@postel.acm.org' => -3.0,
'ietf-123-owner@loki.ietf.org' => -3.0,
'cvs-commits-list-admin@gnome.org' => -3.0,
'rt-users-admin@lists.fsck.com' => -3.0,
'clp-request@comp.nus.edu.sg' => -3.0,
'surveys-errors@lists.nua.ie' => -3.0,
'emailnews@genomeweb.com' => -5.0,
'yahoo-dev-null@yahoo-inc.com' => -3.0,
'returns.groups.yahoo.com' => -3.0,
'clusternews@linuxnetworx.com' => -3.0,
lc('lvs-users-admin@LinuxVirtualServer.org') => -3.0,
lc('owner-textbreakingnews@CNNIMAIL12.CNN.COM') => -5.0,

# soft-blacklisting (positive score)
'sender@example.net' => 3.0,
'.example.net' => 1.0,

},
], # end of site-wide tables
});

1; # ensure a defined return


As you see $final_spam_destiny is set to D_DISCARD but I'm still getting spam that is being labeled but not discarded.

here is an example header from an email that got through:

Return-Path: <xxxx@xxxx.com>
Received: from localhost (localhost [127.0.0.1])
by host.example.com (Postfix) with ESMTP id 10E811007B8
for <user@example.com>; Tue, 7 Jul 2009 12:59:46 +0000 (UTC)
X-Virus-Scanned: Debian amavisd-new at host.example.com
X-Spam-Flag: YES
X-Spam-Score: 19.043
X-Spam-Level: *******************
X-Spam-Status: Yes, score=19.043 tagged_above=3 required=6
tests=[BAYES_99=3.5, HELO_DYNAMIC_HCC=4.295, HTML_IMAGE_ONLY_20=1.546,
HTML_MESSAGE=0.001, HTML_SHORT_LINK_IMG_3=0.001, MIME_HTML_ONLY=1.457,
RCVD_IN_PBL=0.905, RCVD_IN_SORBS_DUL=0.877, RDNS_DYNAMIC=0.1,
URIBL_AB_SURBL=1.86, URIBL_JP_SURBL=1.501, URIBL_OB_SURBL=1.5,
URIBL_WS_SURBL=1.5] autolearn=spam
Received: from host.example.com ([127.0.0.1])
by localhost (host.example.com [127.0.0.1]) (amavisd-new, port 10024)
with ESMTP id FEEQMtUdyjCV for <user@example.com>;
Tue, 7 Jul 2009 12:59:39 +0000 (UTC)
Received: from bl8-161-37.dsl.telepac.pt (bl8-161-37.dsl.telepac.pt [85.241.161.37])
by host.example.com (Postfix) with ESMTP id 8513010075D
for <user@example.com>; Tue, 7 Jul 2009 12:59:37 +0000 (UTC)
From: sapmmer@spamhost.com
To: user@example.com
Subject: ***SPAM*** For you
Content-Type: text/html; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Message-Id: <20090707125938.8513010075D@host.example.com>
Date: Tue, 7 Jul 2009 12:59:37 +0000 (UTC)

till
8th July 2009, 01:24
You have to edit the 50-user file and not 20-debian_defaults