DavidR
3
Just the detection name on its own, isn’t sufficient to hazard a guess. The contents of the MBAM log might help us to help you.
MBAM detects stuff that avast isn’t even looking for in some cases, like this it could could be a file and PUPs aren’t scanned for by default. So that may be why, but MBAM also checks settings in the registry which if changed could be unwanted, though I think that this would produce a different warning.
PUP = Potentially Unwanted Program - See http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci1066761,00.html. Not included in this definition are tools which can be used for good or evil, some have been legitimately installed for a specifically good purpose, but could have been unknowing installed for a malicious purpose.
Not all antivirus programs scan for PUPs and avast has it turned off by default (an exception being the boot-time scan). Generally the avast default settings provide a good balance between protection and performance.
They also try not to have the user involved in too many decisions, when PUP scanning is enabled this is more likely to happen (not directly). Avast would still seek to have the Shield settings Action set to Move to chest.
However, in the on-demand scan the detections would be listed at the end of the scan and this is where the user may decide to change the action from Move to chest to another action. This is where the problem lies to be able to make that decision an informed decision needs to be made and you need the knowledge on the file/program being detected to make that decision. This is I believe why avast doesn’t enable scanning for PUPs by default (other than the boot-time scan previously mentioned).
Clean, quarantine or delete
http://antivirus.about.com/b/2007/03/11/clean-quarantine-or-delete.htm