Vanta agrees to buy AI agent security firm Pillar Security

Vanta agrees to buy AI agent security firm Pillar Security

9 November 2026: Vanta, the compliance automation company, has signed a definitive agreement to acquire Pillar Security, a company founded in 2023 that tests AI agents and blocks their unauthorised actions while they run. Neither company's announcement gives a price or a closing date, and Vanta says the first Pillar-based features reach customers in January 2027.

Not yet independently verified. Neither Vanta nor Pillar states a price; the figure of about $150 million comes from a press report and is unconfirmed. The closing date and conditions of the deal are not stated. We will update this when it can be confirmed, and remove this note.

Four capabilities, four dates

Vanta's post sets out what Pillar's technology will become inside its platform:

• AI Inventory, January 2027: automatic mapping of AI applications, agents, models and MCP servers, tied to owners, approved use cases, data access, vendors, risks and controls.
• Runtime monitoring and detection, January 2027: detection of suspicious activity and guardrail violations, prioritised with context from Vanta's Trust Graph.
• Red teaming, Spring 2027: adversarial testing tailored to the customer's own business.
• Runtime enforcement, Summer 2027: blocking unauthorised actions before they happen.

Vanta says AI Governance by Vanta will be a paid offering from January 2027. The ability to stop an agent in the act is the last item on the list, so for the first months customers get visibility and alerts rather than a block.

Tying the agent to the policy

Vanta argues that AI security point solutions detect threats but lack the business context to rank them, while traditional compliance systems keep that context in policies that can drift from reality. Its plan is to connect Pillar's runtime protection and adversarial testing to the Trust Graph, which it describes as a live map of a trust programme powered by more than 400 integrations.

Vanta gives an example. If an agent tries to reach restricted data, or to share sensitive financial information in an unapproved channel, the platform will block it. The Vanta Agent then alerts the owners and writes an audit trail of which protections were enforced. That describes the planned product, not one customers can switch on today.

IDC's Phil Harris, quoted in Vanta's post, describes the market as "shifting from AI governance on paper to governance at runtime."

What Pillar brings

Pillar says it discovers, tests and secures AI applications and agents across their lifecycle. Its research team has reported flaws rated CVSS 10, among them a sandbox escape in n8n and a flaw in Google's Gemini CLI that let a single GitHub issue compromise its supply chain.

The team also wrote SAIL, a framework for securing AI agents that Vanta says is aligned with ISO and NIST standards and OWASP guidance. Pillar says SAIL has passed 50,000 downloads and maps 91 AI risks across seven lifecycle phases. Vanta says more than 20,000 companies use its platform.

"An agent can cross a line in a single action, long after its last review," said Dor Sarig, Pillar's co-founder and chief product officer.

A price that only the press has reported

Refresh Miami, citing the Israeli publication Calcalist, reports that Vanta will pay approximately $150 million in cash and stock, and that Pillar's team of more than 20 employees will become Vanta's Israeli research and development centre. Refresh Miami describes Vanta as San Francisco-based and notes that the two companies did not disclose a price in their announcements.

Neither Vanta's post nor Pillar's says when the deal is expected to close.

Company profile on TrustList: Pillar Security

Sources

• Vanta: Vanta + Pillar, The System of Runtime Action for AI Governance, 9 November 2026, 9 November 2026
• Pillar Security: Vanta to Acquire Pillar Security, Building Trust in AI, Together, 9 November 2026, 9 November 2026
• Refresh Miami: Months after setting its sights on Miami, AI security startup Pillar to be acquired by Vanta, 10 November 2026, 10 November 2026