This book constitutes revised papers from the 6th International Workshop on Graphical Models for Security, GraMSec 2019, held in Hoboken, NJ, USA, in June 2019.

The 8 full papers presented in this volume were carefully reviewed and selected from 15 submissions. The book also contains two invited talk. The contributions deal with the latest research and developments on graphical models for security.

Inhalt
Invited Papers.- Graph Models in Tracking Behaviors for Cyber-Security.- Attack tree series: a case for dynamic attack tree analysis.- Attack Trees.- Attack trees: a notion of missing attacks.- Optimizing System Architecture Cost and Security Countermeasures.- Security Analysis of IoT systems using Attack Trees.- Attackdefense trees for abusing optical power meters: A case study and the OSEAD tool experience report.- Risk Management and Attack Graphs.- Quantifying and Analyzing Information Security Risk from Incident Data.- Poster Support for an Obeya-like Risk Management Approach.- Conceptual Abstraction of Attack Graphs - a Use Case of securiCAD.- High-level Automatic Event Detection and User Classication in a Social Network Context.