Increase in Spam Score After Upgrading to Version 6.0.7
In the upgrade to 6.0.7, the spam-assassin cf files were updated using the latest files provided by SpamAssassin. In these files there has been a number of changes to the way SpamAssassin will score messages. The following are changes that have been made that has significantly increased the spam score
RCVD_IN_PBL score in 6.0.6 was 0.905, in 6.0.7 the score is now 3.335. To return this score back to the 6.0.6 level, you will need to make the following changes:
Go to /opt/zimbra/conf/spamassassin/ and edit 50_score.cf file, locate and change score RCVD_IN_PBL 0 3.558 0 3.335 # n=0 n=2 To score RCVD_IN_PBL 0 0.509 0 0.905 # n=0 n=2 Edit STATISTICS-set1.txt file, locate and change 39.995 58.9770 0.0262 1.000 0.94 3.56 RCVD_IN_PBL To 20.145 31.4714 0.1790 0.994 0.65 0.51 RCVD_IN_PBL Edit STATISTICS-set3.txt file, locate and change 39.995 58.9770 0.0262 1.000 0.94 3.33 RCVD_IN_PBL To 20.145 31.4714 0.1790 0.994 0.65 0.91 RCVD_IN_PBL
FREEMAIL_ENVFROM_END_DIGIT was added. SpamAssasin bug 6155 reported that this value is to high and is marking valued messages as spam
DOS_OUTLOOK_TO_MX was added which is causing messages sent by Outlook users to be marked as spam. To prevent this, you will need to comment out the following link from 50_scores.cf which is located at /opt/zimbra/conf/spamassassin.
score DOS_OUTLOOK_TO_MX 2.636 1.449 1.737 2.845
There are a number of other changes that SpamAssassin made. Some Customers have restored the 6.0.6 configuration files. You can download the file form the following link:
To have the system load the changes you will need to restart the spam filter by running;
zmantispamctl stop zmantispamctl start
Note: These files could be replaced the next time you upgrade your system.