Horizon3 Promotes Ellen Sundra to Chief Customer Officer to Advance Customer Success and Security Outcomes
Horizon3 promoted Ellen Sundra to Chief Customer Officer to scale NodeZero customer success.
Horizon3 announced on October 14, 2026 that Ellen Sundra was promoted from Vice President, Customers to Chief Customer Officer. She will oversee Sales Engineering, Customer Success, Support, Enablement, Renewals, and Field CTOs for the NodeZero platform. Sundra joined in December 2024 after nearly 15 years at Forescout, where she had also been Chief Customer Officer. CEO Snehal Antani said more than 7,000 organizations use Horizon3 and cited strong retention and expansion.
- Sundra will lead sales engineering, success, support, enablement, renewals, and field CTOs.
- She joined Horizon3 in December 2024 after nearly 15 years at Forescout.
- Horizon3 says more than 7,000 organizations rely on NodeZero.
- CEO Snehal Antani linked the promotion to retention and revenue expansion.
Full article523 words · extracted from horizon3.ai · click to collapse
Sundra’s expanded remit brings six customer-facing functions under her leadership to help customers realize value faster and deepen adoption of NodeZero.
SAN FRANCISCO, October 14, 2026 — Horizon3 today announced the promotion of Ellen Sundra to Chief Customer Officer. Previously Vice President, Customers, Sundra will oversee Sales Engineering, Customer Success, Support, Enablement, Renewals and Field CTOs, with responsibility for helping customers achieve measurable security outcomes with NodeZero®.
Sundra’s promotion recognizes her leadership in bringing technical expertise and customer advocacy together across Horizon3’s customer-facing teams. Her expanded role connects the guidance organizations receive when evaluating NodeZero with the expertise, training and support they need throughout their use of the platform. The appointment reinforces customer success as central to Horizon3’s growth strategy, with a focus on lasting partnerships, retention and expansion.
“Ellen epitomizes our core value of being customer obsessed. Her technical expertise and customer empathy has played a key role in helping Horizon3 cultivate radical champions that love our product and brand,” said Snehal Antani, CEO and co-founder of Horizon3. “In addition, she’s helped build out the team and processes necessary for us to scale pre-sales and post-sales support to the 7,000+ companies that rely on Horizon3 to improve their cyber resilience, resulting in best-in-class retention and revenue expansion metrics across the globe.”
Horizon3’s NodeZero Proactive Security Platform safely proves which exposures attackers can exploit, what they could achieve and whether fixes close the demonstrated attack paths. Sundra’s organization will help customers put that evidence to work through repeatable testing, informed remediation and verification, and expand their use of the platform as their security needs evolve.
“Every team I lead shares responsibility for the customer’s success,” said Sundra. “Customers should be able to count on us to understand their priorities, give them clear technical guidance and follow through as their needs change. My focus is on helping their teams become confident, effective users of NodeZero, with the knowledge and support to turn findings into verified fixes. That is how we earn long-term partnerships and help customers keep reducing risk.”
Sundra joined Horizon3 in December 2024 and brings decades of technical and customer leadership experience. Before joining the company, she spent nearly 15 years at Forescout, advancing from Federal Systems Engineer through global systems engineering leadership to Chief Customer Officer. Her career combines deep cybersecurity expertise with experience building customer-focused teams and working across practitioners, executives and boards.
About Horizon3
Horizon3, the AI-Native Proactive Security Company behind NodeZero®, shifts the advantage from attackers to defenders by giving organizations the power to fight AI with AI. NodeZero, the World’s Best AI Hacker™, autonomously tests defenses at machine speed, safely uncovers and prioritizes exploitable attack paths, instantly verifies fixes, and drives a continuous hack, fix, verify loop. More than 7,000 organizations, including global defense agencies, Fortune 10 enterprises, multinational banks, and major healthcare providers, trust Horizon3 for security they can prove. Horizon3 was recently named the Fastest Growing Cybersecurity Company in North America by the Deloitte Technology Fast 500 and named one of the Most Innovative companies by Fast Company in 2026. Follow Horizon3 on LinkedIn and X.
Media Contact
Dylan Martinez
press@horizon3.ai