First of all, the whole idea of genetic algorithms is still being debated, i.e. if genetic algorithms are in any way better suited to solving optimization problems than other methods (who are either proven, easier to use, or provide other advantages).
That being said, yes, I know of a security-related application of genetic algorithms, mainly used in fuzzing to optimize code paths and therefore code coverage. There is a paper called Vulnerability analysis for x86 executables using genetic algorithm and fuzzing and a BlackHat presentation predating that paper by two years called "Sidewinder": An Evolutionary Guidance System for Malicious Input Crafting