I downloaded CIS AV v12061 and installed it in 'Safe Mode'; CIS updated to "current" AV defs updated w/out a prollem.
I did that TWICE because of issues speciific to my machine.
That notwithstanding, each time CIS AV defs updated w/out ANY issue whatsoever by CIS (after restoring from CIS AV v12061.
I just did the CIS AV update to v12105 - CIS AV def were previously not up to date - and I'm good to go.
If one can not downlod the latest CIS AV .Z file there MUST be at the very least a RAM problem.