new key logger???

[HarryProudy]

Hello,
I recently gave a guy to use my computer. But later I learned that he was experimenting with key loggers. He cannot be very good at it since he does not know much of lower level programming but I'm not sure. A full scan with Avast Free (up to date) came up clean. But if the key logger is made by himself and hasn't been released to the internet yet, will Avast catch it? How can I be sure that he hasn't installed a key logger in my computer? Please help. 

[DavidR]

Keyloggers would fall under the category of PUPs (Potentially Unwanted Program) and by default PUPs aren't scanned for. I believe because many such tools (can be used for good or evil) would be considered PUPs and the majority of users wouldn't know what a PUP is if it bit them.

You can however, enable the option to scan for PUPs in the on-demand scans and for the file system shield, settings.

That may well detect the keylogger as a PUP, it does however require a degree of knowledge of what is installed on the users system and what it does.

[pk]

If his keylogger is made by himself, then avast is not able to detect it. The most keyloggers use standard Windows API functions to capture key strokes, there's nothing wrong with these APIs (they're also used for legitimate reasons in other apps). You can also check which apps are currently running in your system (Task Manager), or use some other tools which detect 3rd party keyloggers (in the case he downloaded a known keylogger from internet).