1. A method comprising: intercepting, by a kernel mode driver of a computer system, file system or operating system activity relating to a first code module initiated by a running process associated with a second code module; selectively authorizing, by the kernel mode driver, loading of the first code module by the running process based at least in part on one or more attributes of the second code module, wherein said selectively authorizing comprises determining whether the second code module comprises a script interpreter; if said determining whether the second code module comprises a script interpreter results in an affirmative determination, then authenticating a cryptographic hash value of the first code module with reference to a multi-level whitelist, the multi-level whitelist comprising (i) a global whitelist database remote from the computer system and maintained by a trusted service provider, the global whitelist database containing cryptographic hash values of approved code modules, which are known not to contain viruses or malicious code and (ii) a local whitelist database containing cryptographic hash values of at least a subset of the approved code modules; and wherein the kernel mode driver is implemented in one or more processors and one or more computer-readable storage media associated with the computer system, the one or more computer-readable storage media having instructions tangibly embodied therein representing the kernel mode driver that are executable by the one or more processors.