AIR Security launches AI agent firewall with $50m funding

AIR Security has emerged from stealth with $50m in funding and a firewall product, also called AIR, designed to protect AI agents. The round was led by Sequoia Capital and Greenoaks, with participation from unnamed industry angels.

The company’s research found more than 17,800 public AI add-ons, representing 6.7 million installations, relying on untrusted external instruction sources, and AI skills impersonating companies such as Anthropic and OpenAI to bypass security reviews and execute arbitrary code.

AIR’s firewall discovers and evaluates every skill, plugin, MCP server and add-on across an organisation’s AI agent supply chain, before and after deployment. It screens for external instruction sources, hidden behaviours and typo-squatted packages, and can revoke access to malicious or unapproved add-ons across the organisation.

The company was founded by CEO Yair Saban and CTO Niv Hoffman, with Ryan Knisley, former CISO at The Walt Disney Company and Costco Wholesale, joining as chief strategy officer.