TRAIL LOG ANALYSIS SYSTEM, MEDIUM STORING TRAIL LOG ANALYSIS PROGRAM, AND TRAIL LOG ANALYSIS METHOD

摘要

A trail log analysis system detects a fraudulent operation from a trail log of an information system, and confirms the correctness of a system action. An information development device generates an information development table from a trail log to be analyzed. The information development table defines a subject (who), an object (what), and an action (what is to be done) as comparison targets, and counts and record an event occurrence number corresponding to an event occurrence time recorded in a trail log for each combination of comparison targets. An accumulation device generates an accumulative information development table by accumulating the information development table corresponding to a trail log recorded previously and up to a time point immediately before the last collected trail log to be analyzed. A comparison device compares the information development table with the accumulative information development table, and outputs a comparison result.