Security Basics mailing list archives
Re: Good SPAM filter for Outlook for use in a small non-profite ORG
From: "Mario A. Spinthiras" <mario () netway com cy>
Date: Thu, 28 Sep 2006 09:38:17 +0300
Devdas Bhagat wrote:
Indeed i agree. Receiving and bouncing isnt necessarily a bad thing though. I agree its a waste of bandwidth since your already downloading the message. Today's world is full of high speed connections though so doesnt really matter. Plus taking into consideration the fact that if its a virus , an author will make the malicious code as small as possible in order for the end-user-stupid-user to download it nice and fast. That includes spam too. Spammers make the messages very crafty and simple.On 24/09/06 16:50 +0300, Mario A. Spinthiras wrote:Is there a way to implement RBL within an email client ? If so you dontSpamAssassin or equivalent.need much of the super duper applications written today to stop spam. RBL usually works perfectly on mail servers. I dont see how it couldntDNSBLs are supposed to be used on MX hosts. anything beyond that leads to accept, then bounce scenarios, or merely tagging as spam. Devdas Bhagat --------------------------------------------------------------------------- This list is sponsored by: Norwich University EARN A MASTER OF SCIENCE IN INFORMATION ASSURANCE - ONLINEThe NSA has designated Norwich University a center of Academic Excellence in Information Security. Our program offers unparalleled Infosec management education and the case study affords you unmatched consulting experience. Using interactive e-Learning technology, you can earn this esteemed degree, without disrupting your career or home life.http://www.msia.norwich.edu/secfocus ---------------------------------------------------------------------------
I have been working on a basic code to slowly develop into something transparent for *nix users between the POP3 and the Email client. Code is as below. Just to make some minds think. Its far from finished but it will definitely inspire.
BEGIN CODE---------------------------------- #!/bin/sh echo "[*] Spam Check Tool" echo "[*] Mario A. Spinthiras (mario at netway dot com dot cy)" echo "" echo "" if [ -z $1 ]; then echo "Not enough parameters." echo "Usage: $0 [host]"; echo "" echo "Application Terminated!" exit; fi echo "[*] Initializing Application..." YESRBL="0" NORBL="0" RBLNUM="0" RBLHOST=$1 FINALNUM="0"RBLS="in.dnsbl.org sbl.spamhaus.org whois.rfc-ignorant.org relays.ordb.org nonconfirm.mail-abuse.org dialups.mail-abuse.org dnsbl.njabl.org dnsbl.sorbs.net list.dsbl.org multihop.dsbl.org multihop.dsbl.org"
for i in $RBLS; do RBLNUM=$(echo $RBLNUM + 1|bc -l) done echo "[*] RBL lists available: $RBLNUM" echo "[*] Checking for mail servers." OUTPUT=$(host -t MX $RBLHOST|awk '{ print $7 }'|sed -e 's/.$//g') if [ -z "$OUTPUT" ]; then echo "[*] Could not retreive mail servers for the requested domain." echo "[*] Exiting." exit; fi for g in $OUTPUT; do FINALOUT="$g $FINALOUT" done echo "[*] Mail servers: $FINALOUT" for i in $FINALOUT; do FINALNUM=$(echo $FINALNUM + 1|bc -l) done echo "[*] Mail Servers to query: $FINALNUM" echo "[*] Performing dns queries.." for a in $FINALOUT; do IPTEMP="" IPTEMP=$(nslookup $a|grep Address|grep -v "#"|awk '{ print $2 }') if [ -z "$IPTEMP" ]; then echo "[*] Could not resolve mail server." echo "[*] Exiting." exit; else IPFINAL="$IPTEMP $IPFINAL" IPTEMP=$(echo $IPTEMP|sed -e "s/^M//") echo "[*] MX: $a is $IPTEMP" IPFINAL=$(echo $IPFINAL|sed -e "s/^M//") fi done echo "[*] Setting up RBL query..." for t in $IPFINAL; do PERFORM="$PERFORM $(echo $t|sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//')" done echo "[*] Reverse Ready: $PERFORM" echo "[*] Checking RBL lists..." for v in $RBLS; do for x in $PERFORM; do QUERYRBL="" QUERYRBL=$(nslookup $x.$v|grep Address|grep -v "#"|awk '{ print $2 }') if [ -z "$QUERYRBL" ]; then NORBL="$(echo "$NORBL +1"|bc -l)"echo "[*] NO!: $v - ($(echo $x|sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//'))"
else YESRBL="$(echo "$YESRBL +1"|bc -l)" YESHOST="$(echo $YESHOST $x|sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//')"echo "[*] YES!: $v - ($(echo $x|sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//'))"
fi done done echo "[*] Finished queries!" echo "[*] Not Passed: $YESRBL" echo "[*] Passed: $NORBL" END CODE----------------------------------------------- --------------------------------------------------------------------------- This list is sponsored by: Norwich University EARN A MASTER OF SCIENCE IN INFORMATION ASSURANCE - ONLINEThe NSA has designated Norwich University a center of Academic Excellence in Information Security. Our program offers unparalleled Infosec management education and the case study affords you unmatched consulting experience. Using interactive e-Learning technology, you can earn this esteemed degree, without disrupting your career or home life.
http://www.msia.norwich.edu/secfocus ---------------------------------------------------------------------------
Current thread:
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG, (continued)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG acuellar (Sep 22)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Dave Ockwell-Jenner (Sep 22)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG John R. Dennison (Sep 22)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Greg Bur (Sep 22)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG LHartung (Sep 26)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG me (Sep 22)
- RE: Good SPAM filter for Outlook for use in a small non-profite ORG Jordan Jason (Sep 22)
- RE: Good SPAM filter for Outlook for use in a small non-profite ORG Beauford, Jason (Sep 22)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Mario A. Spinthiras (Sep 25)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Devdas Bhagat (Sep 27)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Mario A. Spinthiras (Sep 28)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Mario A. Spinthiras (Sep 28)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG Mario A. Spinthiras (Sep 25)
- Re: Good SPAM filter for Outlook for use in a small non-profite ORG iamdotcomguy (Sep 22)