1. A computer-implemented system for processing an update of installed software, the system comprising: at least one computer system having at least one installed application; a test module configured to receive the update and data reflecting vulnerabilities covered by the update and select a testing environment for the update based on information about the update, including information about severity and frequency of exploitation of the vulnerabilities; an analysis module configured to analyze test results of the update and determine a feasibility of installation of the update based on feasibility rules; an installation module configured to receive the update from the analysis module and to install the update on the computer system; and an application and hardware database accessible by the test module; and wherein the test module acquires data from the application and hardware database for selecting the testing environment; and wherein the test module also selects the testing environment based on any of: complexity of update testing; installed application usage frequency; and computer system usage frequency.