CISO Tribune

Vendor comparison · 2 companies

Assail vs Horizon3.ai

Assail sells Ares, an autonomous offensive security platform that tests applications, APIs, mobile apps and AI systems and shows what an attacker could actually reach. 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. 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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  • Assail
  • Horizon3.ai
Assail vs Horizon3.ai: Products, Customers and Funding Compared
AssailAssail sells Ares, an autonomous offensive security platform that tests applications, APIs, mobile apps and AI systems and shows what an attacker could actually reach.assailai.comHorizon3.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.ai
What it sells
  • Ares[1][3][4][5][6][7][9][10][11][12]Continuous autonomous red teaming across web applications, APIs, and mobile apps.
  • Reaper[3]Autonomous offensive cyber operations built for military, federal, and intelligence missions.
  • Assail Anywhere[3]Deployment option for the entire platform, including the AI model.
  • 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.
Categories
Headquarters
Not stated on its pagesSan Francisco, United States[1][11]
Founded
Not stated on its pages2019[1][11]
Ownership and funding
Privately heldPrivately held[2][3]
Named customers
Not stated on its pagesNot stated on its pages
Recent news
  • November 4, 2026Assail, Inc. announced Cassandra, a proactive AI agent integrated into its Ares platform, along with expanded threat modeling capabilities tied to autonomous security testing.[11]
  • July 7, 2026Assail Inc. launched Sidewinder, a rebuilt second-generation version of its Ares offensive security platform running on a new 31 billion-parameter model.[12]
  • 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]
G2 and Gartner Peer Insights
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
Who it fits
From its own pages, Assail sells mainly to security teams in manufacturing, financial services, federal and state government, automotive, retail, and defense. Its industry pages address manufacturers, banks and fintech firms, government agencies, vehicle makers, retailers, and defense programs. Assail also says it supports on-premises, air-gapped, own-cloud, and SaaS deployment for organizations that need to keep data under their control.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.
Last verified
October 21, 2026September 27, 2026

Where they overlap

  • Breach simulation and automated pen-testing is the primary category of both Assail and Horizon3.ai.
  • Both are privately held.

Where they differ, field by field

  • Assail is also filed under API security and Mobile security.
  • Assail lists Ares, Reaper and Assail Anywhere. Horizon3.ai lists NodeZero and Endpoint Security Effectiveness.
  • Horizon3.ai is headquartered in San Francisco, United States.
  • Horizon3.ai was founded in 2019.

How they differ

CISO Tribune files both Assail and Horizon3.ai under Breach simulation and automated pen-testing as their primary category, and both companies are privately held. Assail sells Ares, which it describes as continuous autonomous red teaming across web applications, APIs, and mobile apps, and which uses coordinated AI agents to validate what an attacker could reach. CISO Tribune also files Assail under API security and Mobile security. Horizon3.ai sells NodeZero, an autonomous platform that executes real attack techniques in production and is delivered via multi-tenant SaaS. Horizon3.ai also sells Endpoint Security Effectiveness, which labels each action blocked or permitted and maps it to a MITRE ATT&CK TTP.

Assail also sells Reaper, built for military, federal, and intelligence missions, and Assail Anywhere, a deployment option for the entire platform, including the AI model. Assail says it supports on-premises, air-gapped, own-cloud, and SaaS deployment. Horizon3.ai is headquartered in San Francisco, United States, and was founded in 2019. Assail names customers in manufacturing, financial services, federal and state government, automotive, retail, and defense, and one customer, Branch, says Ares helps it increase penetration testing frequency. Horizon3.ai names banks, healthcare systems, energy providers, manufacturers, governments and defense contractors as organizations that rely on NodeZero.

On July 7, 2026, Assail Inc. launched Sidewinder, a second-generation version of Ares, and on November 4, 2026, it announced Cassandra, an AI agent integrated into Ares. Horizon3 announced AI-powered web application pentesting for NodeZero on July 29, 2026, and said on July 15, 2026 that it is taking part in Anthropic's Project Glasswing.

What it sells: Assail

What Ares does[1][3][4][5][6][7][9][10][11][12]
Ares uses coordinated AI agents to discover weaknesses and validate what an attacker could actually reach. It tests authenticated applications through the existing identity provider and tracks changes across known and shadow APIs. Ares delivers the evidence behind each confirmed risk.
What Reaper does[3]
Assail describes Reaper as built for military, federal, and intelligence missions. Assail has expanded Reaper's sovereign deployment architecture to AWS GovCloud and Google Cloud Assured Workloads.

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.

Questions about Assail and Horizon3.ai

What do Assail and Horizon3.ai sell?
Assail sells Ares, Reaper and Assail Anywhere. Horizon3.ai sells NodeZero and Endpoint Security Effectiveness.
Are Assail and Horizon3.ai in the same category?
Yes. Breach simulation and automated pen-testing is the primary category of both on CISO Tribune.
Where are Assail and Horizon3.ai headquartered?
Horizon3.ai is headquartered in San Francisco, United States.
When were Assail and Horizon3.ai founded?
Horizon3.ai was founded in 2019.
Who owns Assail and Horizon3.ai?
Assail is privately held. Horizon3.ai is privately held.
Who are Assail and Horizon3.ai sold to?
From its own pages, Assail sells mainly to security teams in manufacturing, financial services, federal and state government, automotive, retail, and defense. From its own pages, Horizon3.ai sells mainly to security teams that want to test their defenses with real attacks in production.
What have Assail and Horizon3.ai announced recently?
November 4, 2026: Assail, Inc. announced Cassandra, a proactive AI agent integrated into its Ares platform, along with expanded threat modeling capabilities tied to autonomous security testing. 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 Assail

Assail sells Ares, an autonomous offensive security platform that tests applications, APIs, mobile apps and AI systems and shows what an attacker could actually reach.[1]

Assail says Ares continuously tests applications, APIs, mobile apps, and AI systems as they change. Ares follows attack paths, exploits weaknesses, and proves what an attacker could actually reach. Coordinated AI agents extend testing capacity, and Ares tests authenticated applications through the customer's existing identity provider. Ares also tracks changes across known and shadow APIs and delivers the evidence behind each confirmed risk.[3]

Assail describes Ares as combining autonomous red teaming, attack surface management, and Shadow AI discovery across web, API, mobile, and supported AI environments, with applicable MITRE ATLAS coverage. The Ares platform is powered by Assail's domain-adapted model for security reasoning and tool use.[3][7]

On deployment, Assail says Ares can run within the customer's own infrastructure, even in disconnected environments. With Assail Anywhere, the entire platform, including the AI model, deploys on-premises, inside isolated and air-gapped networks, in the customer's own cloud, or through Assail's SaaS. Assail has also announced that it expanded Reaper's sovereign deployment architecture to AWS GovCloud and Google Cloud Assured Workloads.[3]

Assail names Ares, Reaper, and Scorpion as the products taken to the fight. Reaper is described as autonomous offensive cyber operations built for military, federal, and intelligence missions.[3]

Assail publishes industry pages for manufacturing, financial services, federal and state government, automotive, retail, and defense. In manufacturing, Ares validates systems such as ERP, MES, PLM, supplier portals, industrial APIs, and connected products. In financial services, Ares validates APIs, payment rails, mobile banking apps, and open banking integrations. For retail, Ares validates e-commerce web apps, mobile shopping apps, loyalty APIs, and gift card platforms. In automotive it covers telematics APIs, OTA infrastructure, and mobile companion apps.[4][5][6][9][10]

Assail says its team brings 26 years of offensive security experience. Assail also publishes original research on attack techniques and the exploitation of AI and API surfaces. A customer, Branch, says Ares helps its security team increase penetration testing frequency and validate remediations faster.[1][2][3][4][5][6][8]

Assail on the record

Sources

Assail full record

  1. [1]assailai.comAssail · assailai.com · undated page, accessed October 21, 2026 · Tier A
  2. [2]Press releasesAssail · assailai.com · undated page, accessed October 21, 2026 · Tier A
  3. [3]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  4. [4]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  5. [5]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  6. [6]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  7. [7]Automotive | AssailAssail · undated page, accessed November 4, 2026 · Tier A
  8. [8]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  9. [9]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  10. [10]Assail | Autonomous Offensive AI for the modern application stackAssail · undated page, accessed November 4, 2026 · Tier A
  11. [11]Assail Introduces Cassandra, a Proactive AI Agent Connecting Threat Modeling with Autonomous Security TestingPR Newswire · published November 4, 2026 · Tier A
  12. [12]Assail launches Sidewinder, an offensive security AI that fixes its own mistakesSiliconANGLE · published July 7, 2026 · Tier B

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

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