Filigran OpenAEV is an open-source Adversarial Exposure Validation (AEV) platform that enables organizations to simulate real-life attack scenarios and validate their security posture. The platform utilizes threat intelligence to create and execute attack simulations based on MITRE ATT&CK techniques. OpenAEV allows security teams to build attack scenarios ranging from simple to complex, leveraging prioritized threat intelligence from OpenCTI. The platform supports a "bring your own EDR" approach, enabling seamless execution without requiring additional endpoint agents, though a hybrid approach is also available. The platform includes a library of curated scenarios covering MITRE ATT&CK techniques, with customizable payloads and scenarios. It incorporates AI capabilities to accelerate scenario creation and provide remediation guidance with risk-based prioritization and sequencing. OpenAEV provides continuous monitoring through scheduled recurring scenarios and alerting capabilities. The platform generates reports and findings to track performance improvements over time across different security platforms. It can emulate multiple threat vectors including network infiltration, lateral movement, phishing, endpoint and gateway attacks, and malware/ransomware scenarios. The platform is available in three deployment options: Community Edition (open-source, self-hosted), SaaS (fully managed by Filigran), and Enterprise Edition (with advanced automation and AI features). OpenAEV integrates with OpenCTI for threat intelligence-led simulation capabilities.