A system for continuous monitoring and autonomous detection of patterns in the main memory subsystem of a computer system. The invention can be embodied as an extension to existing memory scrubbing hardware to permit stored code pattern analysis and identification during the autonomous transparent memory scrubbing process. A library of stored target signatures is provided to which code signatures are compared during analysis. Code signatures may be derived directly from the memory subsystem data pattern or may be indirectly and more efficiently derived from the error correction code (ECC) string associated with the stored data pattern. This invention is directly applicable to computer virus detection and neutralization systems.