What Is DLL Hijacking? Understanding and Preventing the Threat

**Executive Summary:** This briefing explains DLL hijacking as an enduring and low-noise technique for executing unauthorized code by abusing Windows DLL load order; it covers the attack chain, notable real-world usages (e.g., Stuxnet, PlugX, Cobalt Strike), why legacy and vendor-supplied software keep the risk high in 2025, and recommended detection and mitigation measures (EDR telemetry, DLL path monitoring, signing and ACLs, SafeDllSearchMode, AppLocker/WDAC and secure coding/vendor review) to reduce supply-chain and post-exploitation exposure.