The STRIDE Methodology for Threat Identification

STRIDE is the most widely adopted threat modeling methodology, originally developed by Microsoft, and it organizes the search for threats into six categories represented by its acronym: Spoofing, or identity impersonation; Tampering, or unauthorized data manipulation; Repudiation, or the ability to deny having performed an action without leaving evidence; Information disclosure, or exposing information to someone who shouldn't have access; Denial of service, or disrupting the system's availability; and Elevation of privilege, or obtaining permissions higher than those legitimately granted. Its practical value is that it offers a structured, memorable checklist applied systematically to each component and data flow in the application diagram, forcing the team to explicitly consider all six categories instead of stopping at the threats that are most obvious or familiar to each session participant. An important nuance is that not all categories apply with the same relevance to every component: a data store rarely faces direct spoofing threats, but it's highly relevant for information disclosure and tampering, so applying STRIDE with judgment, prioritizing the categories truly pertinent to each element, is more productive than applying it mechanically and uniformly across the whole system.