OAuth grants are the quiet back door of modern SaaS, and the rise of remote MCP servers is only making that back door wider. Every time an employee clicks “Sign in with Google” or hooks an AI agent to a new MCP server, another vendor gets a key to your data, often without IT or security in the loop. Most of those grants are low-risk. Some are not. This checklist gives you a repeatable way to tell the difference before a permissive scope turns into an incident.
What you’ll learn:
- When to run an OAuth investigation, and which grants deserve the most scrutiny
- The four pillars every grant should be evaluated against: scopes and permissions, app registration details, vendor trust signals, and app popularity and usage
- Red flags that separate a legitimate integration from an overreaching or malicious one
- What makes MCP server connections different, and where to apply extra checks
- A decision matrix for what to keep, what to restrict, and what to revoke
Who this guide is for:
Security leaders, IT admins, and GRC practitioners who need a repeatable way to evaluate OAuth grants and MCP server connections before they turn into supply-chain risk.
