Correlating Evidence from Multiple Sources

Evidence correlation consists of cross-referencing information from independent sources, such as firewall logs, authentication records, traffic captures and endpoint artifacts, to confirm or rule out hypotheses with a level of certainty no single source could offer on its own. In practice, no individual record tells the whole story: an access log may show a suspicious IP, but only by correlating it with network traffic and endpoint events can you confirm whether that connection actually resulted in a compromise or was a failed attempt. This process also helps detect inconsistencies that reveal evidence tampering, such as a file whose modification date doesn't match the access records of the system where it was supposedly created. Mastering correlation reduces false positives and keeps the investigation from relying on a single data source that could be incomplete, corrupted or deliberately altered by the threat actor.