Messaging Gateway sends an alert message indicating that the bmserver has crashed on a signal 11 and an exit code of 0x008B.
Decomposition of the message attachment has resulted in runaway recursion which eventually caused the process to be terminated.
This issue has been resolved with the SMG 10.6.2 release.
This was an issue when processing some poorly constructed message attachments when the "MIME fuzzy main header" option is set in Protocols >> Settings >> Content Scanning >> Advanced. The affected process is automatically restarted as part of the Messaging Gateway automated crash recovery and any messages being filtered will be automatically reprocessed. If this occurs frequently then unchecking "MIME fuzzy main header" in Protocols >> Settings >> Content Scanning >> Advanced will allow SMG to treat these messages as unscannable.