Multifactor develops zero-trust authentication, authorization, and auditing infrastructure for AI agents and humans. Using patented post-quantum cryptographic techniques, it lets people share online accounts securely through revocable 'checkpoint links' without ever exposing passwords or underlying credentials. For AI agents, Multifactor provides a provably safe execution environment that prevents prompt injection, password theft, confused-deputy attacks, and cross-agent hijacking. The company was built on a decade of cybersecurity research and is part of Y Combinator's Fall 2025 batch.
Multifactor
ActiveZero-trust authentication, authorization, and auditing for AI agents
Total raised
$15.5M
2 rounds
Stage
Seed
Dec 2025
Team
1-10
since 2025
Pricing
—
Founded
2025
San Francisco, United States
Agent-ready
—
Zero-trust authentication, authorization, and auditing for AI agents and humans
Patented post-quantum cryptographic techniques
Revocable 'checkpoint links' for secure account sharing
Shares accounts without exposing passwords or credentials
Provably safe execution environment for AI agents
Defends against prompt injection attacks
Prevents password theft and confused-deputy attacks
Blocks cross-agent hijacking
12/100
Early
MCP server
Public API
Webhooks
OAuth 2.0
SDKs
No public agent surfaces detected yet.
Cumulative raise
From 2025 to 2026 · 2 rounds tracked
Total
$15.5M
Dec 2025 Seed $15M ● Nexus Venture Partners
Jan 2025 Seed $500K ● Y Combinator
Capital network
$15.5M raised ·8 backers·10 network links
- Backers8
- Shared portfoliocompanies these backers also fund
- Extended networkfunds that co-invest alongside them
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- What does Multifactor protect?
- It provides zero-trust authentication, authorization, and auditing for both AI agents and humans, securing how they access and share online accounts.
- How does secure account sharing work?
- Multifactor uses revocable 'checkpoint links' so people can share accounts without ever exposing passwords or underlying credentials.
- What agent-specific threats does it address?
- It aims to prevent prompt injection, password theft, confused-deputy attacks, and cross-agent hijacking through a provably safe execution environment.
- What is its technology based on?
- Multifactor uses patented post-quantum cryptographic techniques and was built on a decade of cybersecurity research. It is part of Y Combinator's Fall 2025 batch.
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