Following the update to Messaging Gateway (SMG) 10.7.5, the SMG systems begin sending admin alert messages from "bad-msg-monitor" with the subject "Bad message found":
Subject: Bad message found
The Symantec Messaging Gateway has determined that one or
more email messages are destabilizing the filtering process.
These messages are listed below and have been placed into
the Bad Message queue.
You may view and act on these messages from the command line
with the mta-control bad-msg command set.
Refer to the Symantec Messaging Gateway Administration Guide
for more information about the mta-control command.
Time: Tue, 02 Nov 2021 21:17:10 -0700
Release : 10.7.5
Component : URL modification
A defect in SMG 10.7.5 is preventing messages with an empty Subject header or misidentified content encoding from being processed by the URL modification feature.
Some instances of this issue are resolved in Messaging Gateway 10.8.0.
For Messaging Gateway version 10.7.5 please update to version 10.8.0 or apply patch 10.7.5-292 as follows:
smg [10.7.5-4]> patch list
sms-appliance-patch.x86_64 10.7.5-292 symrepo_smg_patches
smg [10.7.5-4]> patch -p 10.7.5-292 install
Messages with an empty Subject header can be exempted from URL modification processing by adding a clause to the URL modification content filtering policy similar to the entry below:
As with all changes to Content Filtering policies, any change should be carefully tested using a limited set of test users before applying the change to larger groups of end users.