This document presents a security threat analysis for routing over low power and lossy networks (LLN). The development builds upon previous work on routing security and adapts the assessments to the issues and constraints specific to low power and lossy networks. A systematic approach is used in defining and evaluating the security threats. Applicable countermeasures are application specific and are addressed in relevant applicability statements. These assessments provide the basis of the security recommendations for incorporation into low power, lossy network routing protocols.