Anti-Spam 3.0 Maintenance Pack 1 (MP1)

What's new?

The following improvements have been introduced since Kaspersky Anti-Spam 3.0.242.0:

1. Improved filtering methods.
   
   Methods for fighting the so-called "graphic" spam (that is methods used for analyzing graphic attachments, processing animated images, etc.) have been improved. In particular:
   • Technology GSG-7 for processing and identification of similar images with textual content has been introduced.
   • Animated images are now processed using GSG-A technology that allows extracting relevant important frames from the animation.
2. UDS: data transfer protocol has been extended, an ability to repeat requests in order to rule out the possibility of accidental loss of packages between KAS 3.0 MP1 and UDS servers has been added.

Changed Features

The following problems have been fixed since Anti-Spam 3.0.242.0:

• The stat application used for collecting statistics could exit with an error if it encountered extra long lines in the e-mail messages processing log /usr/local/ap-mailfilter3/log/filter.log
• If an error occurred when the e-mail message was returned to the original process q-mail, module kas-qmail used for integration with qmail did not return the corresponding error to the SMTP sessions.
• In some cases kas-license module used for verification of the license policy could exit with an error.

General Issues & Workarounds

• In certain Linux distributions, when the ServerSpareFilters value is set to 1 or greater, and the application is restarted with the killall utility (used in kas-restart) a new filtration process may appear before the killall completes its work. The killall utility in that case will return an error and the kas-restart script will inform about its inability to restart the application although it has actually been restarted. Such situation can also occur in cases when the Control Center is used to invoke kas-restart to make the application read its configuration again.
• Correctness of certain parameters in filter.conf is not validated or is validated too strictly.
• When KAS 3.0 is installed and running on the same server with KAS 2.0 or Kaspersky Mail Gateway 5.5, any restart of the filtering processes (ap-mailfilter) by the kas-restart script or the Control Center will cause an attempt to restart the filtering processes of KAS 2.0 and Kaspersky Mail Gateway 5.5 as well. However, the actual restart of the processes belonging to other products is impossible. Consequently, the corresponding warnings will be displayed; they should be ignored.
• Domain names in the lists of e-mail addresses and Protected domains are case-sensitive, therefore we recommend that you enter them using the lower case.
• If the limit for the processed message ClientFilteringSizeLimit is exceeded module of integration with kas-qmail will enter a message of exceeded priority into the log: it is marked as an error, but in fact it is an information message.
• For kas-qmail with parameter ClientOnError set to reject action temporary fail will be displayed in the smtp session during processing of the filtering errors.
• Mandrake package does not include text line editor ed, therefore script /usr/local/ap-mailfilter3/bin/enable-updates.sh does not include UDS on this operating system. You should either install ed before installation of KAS 3.0 or turn on UDS separately using the Control Center or manually by editing configuration file /usr/local/ap-mailfilter3/etc/filter.conf.