Many a time , the ultimate cause of a computer getting infected is ultimately because the critical software’s and those known to have many bugs like adobe flash are not properly updated. This of course is an avoidable situation.

Secunia Personal Software Inspector is a simple software and all you have to do is download a simple under a megabyte software and allow it to scan your PC. The utility can be launched upon installation and it scans your PC right away. It requires an active internet connection to scan your PC.

Note that it may show up as not responding until the pc scanning is complete, also the application interface may remain blank white until the process is over.
After it completes scanning, it displays all software’s which are insecure, with a pie graph showing the percentage. It also scans your HDD for programs and then shows its patched status.

It can be downloaded from :

Download - Personal (PSI) - Vulnerability Scanning - Secunia.com