Leonardo Ribeiro Tessari

Information Security Coordinator with 6+ years of experience across network security, cybersecurity architecture, and OT/ICS security in enterprise and industrial environments.

At Grupo EMS, I lead cybersecurity initiatives across 22 business units in Brazil and operations in Mexico, Serbia, Italy, and the United States. I have led large-scale security transformations, including the migration of 44 physical firewalls from Fortinet to Palo Alto Networks and the standardization of security architecture across the environment.

My hands-on experience includes Palo Alto Networks, Fortinet, Imperva WAF and API Security, AlgoSec FireFlow, CrowdStrike, Cisco ISE, Aruba ClearPass, Darktrace NDR, Nozomi Networks, BeyondTrust, Delinea, and Trend Micro Deep Security, covering network security, NAC, EDR, NDR, PAM, WAF, vulnerability management, and security operations.

I have led initiatives achieving 100% Imperva security compliance across 200 domains, improved firewall security posture by 35%, remediated High and Critical infrastructure vulnerabilities, and implemented EDR coverage across 6,500+ endpoints.

I also bring practical OT/ICS cybersecurity experience in pharmaceutical environments, including industrial network segmentation, Cisco ISE Dynamic VLANs, communications mapping, and security architecture reviews across PLCs, HMIs, HVAC systems, and industrial equipment.

I am particularly interested in Senior Cybersecurity Engineer, Network Security Engineer, Security Architect, and OT/ICS Security opportunities where I can combine hands-on technical expertise with security architecture, technical leadership, and measurable risk reduction.