Anti-Spam Service User`s Guide
Contents
1. enabled a shorter version of the spam report is used This is especially useful when you are not using the attachment feature above e Use Bayes System This application can use a statistical Bayesian analysis system to determine whether each message is spam based on previous examples of spam and non spam e Use Auto Learning This application can automatically train its Bayes database by analyzing messages that have a score that strongly suggests that they are spam or non spam For those who wish not to use the web based interface you will need to know the file structure of the Anti Spam Service On a default installation the following directories are provisioned spamassassin etc mail spamassassin Files located in etc mail spamassassin a bogus virus warnings cf This rule set tries to pick out collateral spam caused by viruses The goal is to catch warnings generated by virus scanners along the lines of you sent us virus which are sent to the usually faked senders of virus infected e mails b chickenpox cf Rule set designed to catch spam like l ooks flor th is kind of sy ta x c local cf The file in which you are able to customize your settings if you have the Enterprise version Below is an explanation of the settings in this file e rewrite_subject 1 Whether to change the subject of suspected spam e report_safe 1 Encapsulate spam in an attachment CUSTOMER_IP is replaced with IP of customer s2. server trusted_networks CUSTOMER_IP 127 0 0 1 e ok_languages en es de Mail using languages used in these country codes will not be marked as being possibly spam in a foreign language e ok_locales en Mail using locales used in these country codes will not be marked as being possibly spam in a foreign language use_bayes 1 Enable the Bayes system auto_learn 1 Enable Bayes auto learning required_hits 8 0 How many hits before a message is considered spam whitelist_from Allow email or domain From header e whitelist_from_rcvd Allow email or domain Received header d sa blacklist uri cf Contains a large set URI s universal resource identifier that have been found in spam messages A URI is the generic set of all names and addresses which are short strings which refer to objects typically on the Internet The most common kinds of URI are URLs and relative URLs Page 6 of 7 Filtering with an email client Once identified the mail can then be optionally tagged as spam for later filtering using the user s own mail user agent application i e Microsoft Outlook or Outlook express etc The email is marked up with the subject line like follows keKKKSPAM Official Prize Claim Form The SPAM part of the subject line is added by AIT s Anti Spam Service User s can setup a filter to move emails with this subject line into a temporary or deletable folder within the mail client The official Prize Claim Fo
3. Page 1 of 7 Anti Spam Service User s Guide Advanced Internet Technologies Inc December 3 2004 Search All Your Favorite Engines from a Single Source with tyBit Revision History Download Now This is version 1 2 2 of the Anti Spam Service User s Guide All updates to this document will be noted below Version 1 2 2 Version 1 2 1 Version 1 2 Version 1 1 1 Version 1 1 Version 1 0 Preface Added Whitelist section Updated the call to spamc to specify the user via LOGNAME Escape asterisks when identifying the X Spam Level when directing to dev null Updating to reflect the appropriate changes in the SMT 4 1 interface as now the SMT 4 1 has control settings for base configurations of the Anti Spam Service Updated the lock file line to have the colon after the fw Updated to reflect documentation for deletion of mail not just marking spam email and also the frequency of automatic restarts of spamd Original Documentation This document is the user manual for the Anti Spam Service offered by AIT Target Audience AIT Customers who use a web hosting account Linux only Page 2 of 7 Table of Contents 1 Background 3 2 Spam Identification Tactics 3 3 Configuration and Configuration Files 3 4 Filtering with an email client 6 5 Deletion of email on the server 6 6 Whitelisting Allowing Email through filtering 7 Page 3 of 7 Background The Anti Spam Service is a mail filt
4. ator Score Threshold Options Low Threshold 5 0 default O Medium Threshold 7 5 O High Threshold 10 0 Rewrite Message Subjects Don t Rewrite Subjects default O Rewrite Subjects using text SPAM Encapsulate Spam in Attachments Don t Use Attachments 0 Use Attachments default 1 O Use Text only Attachments 2 Use Terse Reports Full Report default Terse Report Use Bayes System Use Bayes System default O Disable Bayes System Use Auto Learning Use Auto Learning default Disable Auto Learning Configure Now 2 This tool is designed to make it easier to customize an installation of Anti Spam with some common options After you answer the questions below a configuration file matching your choices will be displayed and you can download it and use it with your installation Score Threshold Anything above the threshold is maked as spam Increasing this threshold will increase the amount of spam missed but will reduce the risk of talse positives Rewrite Message Subjects Choose whether this application should add text at the beginning of the subject line of suspected spam You can also change the text added to the subject Encapsulate Spam in Attachments By default this application encapsulates each message above the spam threshold into a new message as a MIME attachment This prevents dangerous scripting and makes it easy for users to identity wh
5. er to identify spam Using its rule base it uses a wide range of heuristic tests on mail headers and body text to identify spam also known as unsolicited commercial email This document provides basic instruction on how to configure the application as necessary By default no configuration is necessary to use this application once ordered and provisioned Spam Identification Tactics The spam identification tactics used in this service include e Header analysis Spammers use a number of tricks to mask their identities fool you into thinking they ve sent a valid mail or fool you into thinking you must have subscribed at some stage The Anti Spam service tries to spot these e Text analysis Again spam mails often have a characteristic style to put it politely and some characteristic disclaimers and CYA text The Anti Spam service can spot these too e Blacklists The Anti Spam service supports many useful existing blacklists such as mail abuse org ordb org or others e Razor Vipul s Razor is a collaborative spam tracking database which works by taking a signature of spam messages Since spam typically operates by sending an identical message to hundreds of people Razor short circuits this by allowing the first person to receive a spam to add it to the database at which point everyone else will automatically block it For the Enterprise version this is automatically set to grow as necessary For Shared solution customers this
6. ether a message is spam before opening it You can also choose to create text only attachments for increased safety If you disable this option the message is unaltered except for a spam report in the headers Use Terse Reports If this option is enabled a shorter version of the spam report is used This is especially useful when you are not using the attachment feature above Use Bayes System This application can use a statistical Bayesian analysis system to determine aax a Internet The configurations that can be changed are as follows e Score Threshold _Anything above the threshold is marked as spam Figure 3 1 Increasing this threshold will increase the amount of spam missed but will reduce the risk of false positives e Rewrite Message Subjects Choose whether this application should add text at the beginning of the subject line of suspected spam You can also change the text added to the subject e Encapsulate Spam in Attachments By default this application encapsulates each message above the spam threshold into a new message as a MIME attachment This prevents dangerous scripting and makes it easy for Page 5 of 7 users to identify whether a message is spam before opening it You can also choose to create text only attachments for increased safety If you disable this option the message is unaltered except for a spam report in the headers e Use Terse Reports If this option is
7. is capped at 15MB in size as not to contribute towards over disk usage Configuration and Configuration Files The Anti Spam service requires very little configuration you do not need to continually update it with details of your mail accounts mailing list memberships etc It accomplishes filtering without this knowledge as much as possible The Anti Spam service typically differentiates successfully between spam and non spam in between 95 and 99 of cases depending on what kind of mail you get When the Anti Spam Service is provisioned to an account it will enable the web based configuration so it can be used through the SMT 4 1 To utilize the web based feature log into the SMT 4 1 cpanel at http yourdomain cpanel or http your ip address cpanel Click on Additional Services then Manage and then Anti Spam Service You ll see a screen much like what is below in Figure 3 1 Page 4 of 7 Server Management Tool Microsoft Internet Explorer File Edit view Favorites Tools Q sak Q x a LA 2 Search She Favorites media g R e w LJ ay i Links 7 ig oper Server Management Tool smt GD Main Menu gt i Customer Care Center Customer Console Web Services Mail Services FTP Services Additional Services o ene Order Manage EEEE gt Additional Services gt Manage Help Bandwidth Server Info Anti Spam Configuration Gener
8. me which must be present in the Received headers So in case the first is not unique enough the second pattern can be used to be more specific The following definitions will allow incoming email from specific domains to be allowed to be received with a higher score by the anti spam service whitelist_from aitcom net whitelist_from ait com whitelist_from support aitcom net whitelist_from aitdomains com It is recommended that these entries be added to your system if they are not already to allow your account to receive mail from AIT and our support system for processing ticket requests
9. pam assassin to do filtering Ofw spamassassin lock lt 256000 usr bin spamc f p 8061 u SLOGNAME 20 AX Spam Level A e e e lee dev null Note We have found that in some cases the asterisks must be escaped with back slashes in some cases they will work without being escaped 4 Upload the etc procmailrc file back to it s original location Once the updated file has been uploaded your server will recognize the change and begin deleting email that fit the spam criteria If your mail services don t change after the update please check the following Permissions on the etc procmailrc file are set to 640 The permissions can be check with the Is command and changed with the chmod command via ftp Make sure the new rule to delete the spam follows the rule to call spamc in etc procmailrc If the change still doesn t seem to be taking affect contact AIT s Customer Service Department by submitting a ticket at http support aitcom net Whitelisting Allowing Email through filtering Customers with the Enterprise version of the Anti Spam services may modify their local cf file with whitelist definitions Definitions such as whitelist_from_rcvd ait com ait com Will allow all incoming mail with received headers from ait com to be allowed through the anti spam service Note The first parameter is the address or domain you wish to whitelist and the second parameter is the domain na
10. rm is the original subject line of the email Deletion of email on the server This function is currently only available on our managed dedicated server offering I MHIP Enterprise Business Enterprise etc The function is there to delete suspected spam that fits the criteria set forth by your spam engine but remember that the Anti Spam Service is an engine not just a filter It is recommended to mark the potential spam and put those email in a different directory named something like Junk or Junk Mail in your email client An example of this is listed below in Figure 4 1 Deleted Items 4 LA Drafts C GRR Email i Inbox 7 id Junk E mail 6 LA Outbox 3 Sent Items a L Search Folders 3 Personal Folders A neteee a mene Figure 4 1 This means keeping a copy of all or most of your mail separated into spam and good email piles and review your spam email to ensure it is learning properly As for the actual configuration of deletion of email which is not recommended but can be done follow the following instructions 1 Edit the following file etc procmailre 2 Find the following section of text in the file that appears to be like what is listed below Use spam assassin to do filtering O0fw spamassassin lock lt 256000 usr bin spame f p 8061 u SLOGNAME 3 Update the file to look like the configuration below The lines in red are the important changes Page 7 of 7 Use s
Download Pdf Manuals
Related Search