CISO Tribune

Vendor comparison · 2 companies

Horizon3.ai vs Reflex Security

Horizon3.ai sells NodeZero, a platform that autonomously executes real attack techniques in production environments so organizations can find exploitable weaknesses, fix them and verify the fixes. Reflex Security says a breach cannot be controlled, and that a team cannot pick the day, the attacker or the exploit. CISO Tribune files both under Breach simulation and automated pen-testing. This page sets the two records side by side: what each sells, where it is based, who owns and funds it, the customers it names and its recent news, each fact numbered to its source.

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  • Horizon3.ai
  • Reflex Security
Horizon3.ai vs Reflex Security: Products, Customers and Funding Compared
Horizon3.aiHorizon3.ai sells NodeZero, a platform that autonomously executes real attack techniques in production environments so organizations can find exploitable weaknesses, fix them and verify the fixes.horizon3.aiReflex SecurityReflex Security says a breach cannot be controlled, and that a team cannot pick the day, the attacker or the exploit.reflexsecurity.io
What it sells
  • NodeZero[2][3][5][6][7][8][9][10][14]An autonomous platform that executes real attack techniques in production.
  • Endpoint Security Effectiveness[3][7]Tests how endpoint protections respond to real attack behavior.
  • Reflex[1][2][3]A crisis simulation platform that builds a live crisis from a team's real environment and adapts to each decision the team makes.
Categories
Headquarters
San Francisco, United States[1][11]Not stated on its pages
Founded
2019[1][11]Not stated on its pages
Ownership and funding
Privately held[2][3]Not stated on its pages
Named customers
Not stated on its pagesNot stated on its pages
Recent news
  • November 5, 2026Horizon3 appointed Chris Wood as Director of Sales for Australia and New Zealand and Vivienne Horsfall as Growth Marketing Director for Asia Pacific and Japan.[13]
  • July 29, 2026Horizon3 announced an expansion of its NodeZero platform to include AI-powered web application pentesting capabilities.[14]
  • July 15, 2026Horizon3 announced it is taking part in Anthropic's Project Glasswing, an initiative focused on securing critical infrastructure.[12]
Not stated on its pages
G2 and Gartner Peer Insights
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
  • G2: listed, seen November 10, 2026[4]
  • Gartner Peer Insights: Not stated on its pages
Who it fits
From its own pages, Horizon3.ai sells mainly to security teams that want to test their defenses with real attacks in production. It names banks, healthcare systems, energy providers, manufacturers, governments and defense contractors as organizations that rely on NodeZero. Its pages describe customers ranging from the Global 100 to a local hospital.Not written yet
Last verified
September 27, 2026November 5, 2026

Where they overlap

  • Breach simulation and automated pen-testing is the primary category of both Horizon3.ai and Reflex Security.

Where they differ, field by field

  • Reflex Security is also filed under Incident response and forensics and Security awareness training.
  • Horizon3.ai lists NodeZero and Endpoint Security Effectiveness. Reflex Security lists Reflex.
  • Horizon3.ai is headquartered in San Francisco, United States.
  • Horizon3.ai was founded in 2019.
  • Horizon3.ai is privately held.

How they differ

CISO Tribune files Horizon3.ai under Breach simulation and automated pen-testing, and files Reflex Security under that same primary category, with Incident response and forensics and Security awareness training as additional filings. Horizon3.ai sells NodeZero, a platform that autonomously executes real attack techniques in production environments so organizations can find exploitable weaknesses, fix them and verify the fixes. Reflex Security sells Reflex, a crisis simulation platform that builds a live crisis from a team's real environment and adapts to each decision the team makes.

The two differ in what gets exercised: NodeZero is described as running attack techniques without agents or disruption, delivered via multi-tenant SaaS. In a Reflex exercise, the team works a live breach while an adaptive adversary and pressured stakeholders push back in real time, and the exercise tests coordination across technical, legal and executive teams. Reflex produces an after-action report the moment the team finishes. Horizon3.ai also sells Endpoint Security Effectiveness, which labels each action blocked or permitted, and pentesting for compliance that delivers a Penetration Test Report and a Fix Action Report.

Horizon3.ai is headquartered in San Francisco, was founded in 2019, and is privately held. Its pages name banks, healthcare systems, energy providers, manufacturers, governments and defense contractors as organizations that rely on NodeZero. On July 29, 2026, Horizon3.ai announced an expansion of NodeZero to include AI-powered web application pentesting capabilities. On July 15, 2026, it announced it is taking part in Anthropic's Project Glasswing.

What it sells: Horizon3.ai

What NodeZero does[2][3][5][6][7][8][9][10][14]
NodeZero is described as an autonomous platform capable of executing self-directed actions to achieve an objective. Horizon3.ai says it executes real attack techniques without agents or disruption. It is delivered via multi-tenant SaaS.
What Endpoint Security Effectiveness does[3][7]
NodeZero checks for EDR presence on each host. It then executes techniques ranging from credential theft to privilege escalation and lateral movement. Every action is mapped to a MITRE ATT&CK TTP and labeled blocked or permitted.

What it sells: Reflex Security

What Reflex does[1][2][3]
Reflex builds a tailored scenario in minutes, catered to the real environment, tools and threats of the team. The team works a live breach while an adaptive adversary and pressured stakeholders push back in real time. AI agents play every side of the breach and react to each call the team makes.

Questions about Horizon3.ai and Reflex Security

What do Horizon3.ai and Reflex Security sell?
Horizon3.ai sells NodeZero and Endpoint Security Effectiveness. Reflex Security sells Reflex.
Are Horizon3.ai and Reflex Security in the same category?
Yes. Breach simulation and automated pen-testing is the primary category of both on CISO Tribune.
Where are Horizon3.ai and Reflex Security headquartered?
Horizon3.ai is headquartered in San Francisco, United States.
When were Horizon3.ai and Reflex Security founded?
Horizon3.ai was founded in 2019.
Who owns Horizon3.ai and Reflex Security?
Horizon3.ai is privately held.
Who are Horizon3.ai and Reflex Security sold to?
From its own pages, Horizon3.ai sells mainly to security teams that want to test their defenses with real attacks in production.
What have Horizon3.ai and Reflex Security announced recently?
November 5, 2026: Horizon3 appointed Chris Wood as Director of Sales for Australia and New Zealand and Vivienne Horsfall as Growth Marketing Director for Asia Pacific and Japan.

About Horizon3.ai

Horizon3.ai sells NodeZero, a platform that autonomously executes real attack techniques in production environments so organizations can find exploitable weaknesses, fix them and verify the fixes.

Horizon3.ai describes the problem as one of effectiveness. Its pages say that security teams do not have a tools problem, and that many siloed security tools are not designed to work together. The company says the seams between those tools are blind spots that attackers exploit. Horizon3.ai says knowing a vulnerability exists is not enough and that teams need to know whether it is actually exploitable.[5]

NodeZero is described as an autonomous platform capable of executing self-directed actions to achieve an objective. In pentesting, those objectives include becoming Domain Admin, compromising sensitive data and gaining access to critical systems. Horizon3.ai says NodeZero executes real attack techniques without agents or disruption. Horizon3.ai says its autonomous approach is delivered via multi-tenant SaaS.[5]

Horizon3.ai describes a loop of hack, fix, verify and repeat. Its pages say teams should re-test to confirm a threat is gone after a fix. The company also describes a one-click verify tool in NodeZero that starts a targeted retest.[6]

Endpoint Security Effectiveness shows how endpoint protections respond to real attack behavior, and NodeZero checks for EDR presence on each host. Horizon3.ai also sells pentesting for compliance, delivered by OSCP pentesters together with the NodeZero platform.[6][7]

The service delivers a Penetration Test Report and a Fix Action Report.[6]

Horizon3.ai says NodeZero serves customers from the Global 100 to a local hospital. Its pages also name banks, healthcare systems, energy providers, manufacturers, governments and defense contractors as organizations that rely on NodeZero.[5][9]

Horizon3.ai was founded in 2019 and is headquartered in San Francisco, CA. Snehal Antani is its Co-Founder and CEO. The company describes its team as a mix of US Special Operations, US National Security and cybersecurity industry veterans.[4][6][7][8][10]

Horizon3.ai on the record

Sources

Horizon3.ai full record

  1. [1]About usHorizon3.ai · horizon3.ai · undated page, accessed September 27, 2026 · Tier A
  2. [2]Horizon3 raises 250m series e at 2b valuation to lead the ai vs ai cybersecurity eraHorizon3.ai · horizon3.ai · published August 3, 2026 · Tier A
  3. [3]Home | Horizon3.aiHorizon3.ai · undated page, accessed October 25, 2026 · Tier A
  4. [4]Why Continuous Exposure Management Matters for Financial ServicesHorizon3.ai · undated page, accessed October 25, 2026 · Tier A
  5. [5]The Future of Security: Our Vision | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  6. [6]Compliance Solutions for Cybersecurity | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  7. [7]Endpoint Security Effectiveness | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  8. [8]Identity Security Validation | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  9. [9]Why Our Platform Wins | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  10. [10]HomeECB AI Cybersecurity Mandate | NodeZero® | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  11. [11]The Team | Horizon3Horizon3.ai · undated page, accessed November 5, 2026 · Tier A
  12. [12]Horizon3 Joins Anthropic’s Project Glasswing to Help Defend Critical Infrastructure with the Attacker’s PerspectiveHorizon3 · published July 15, 2026 · Tier A
  13. [13]Horizon3 Expands Australia and New Zealand Team, Strengthens APJ InvestmentHorizon3 · published November 5, 2026 · Tier A
  14. [14]Horizon3’s NodeZero® AI Hacker Extends Production-Safe Autonomous Pentesting to Web ApplicationsHorizon3 · published July 29, 2026 · Tier A

Reflex Security full record

  1. [1]reflexsecurity.ioReflex Security · reflexsecurity.io · undated page, accessed November 5, 2026 · Tier A
  2. [2]How ai powered tabletop exercises improve incident response readinessReflex Security · reflexsecurity.io · undated page, accessed November 5, 2026 · Tier A
  3. [3]Reflex SecurityReflex Security · undated page, accessed November 10, 2026 · Tier A
  4. [4]Reflex Security Reviews 2026: Details, Pricing, & FeaturesG2 · undated page, accessed November 10, 2026 · Tier C

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