lots of hung cron jobs

[Peter H. Lemieux]

CentOS 6.10
MailScanner 5.1.3-2

Running "ps ax" on this server this morning brought up over a dozen hung 
cron processes like this:

awk -v progname=/etc/cron.hourly/mailscanner progname {?????   print prognam
/bin/sh /usr/sbin/ms-cron HOURLY
/bin/sh /usr/sbin/ms-check

Any suggestions why this might be happening?

Peter