"A newly joined marketing team member started using an overseas AI transcription tool simply because it was convenient. Logging in via 'Sign in with Google' was effortless, but when I later checked the admin console, that tool had been granted full access to corporate Google Calendar and Gmail. It's a company we've never even heard of. While I don't think it's malicious, I honestly have no idea how many tools like this are currently connected across the company"—we received this inquiry from a professional managing IT duties at a 40-person company. As more work moves to the cloud, employees find and connect tools on their own. Every single connection acts as an entry point into corporate data.
Options like "Sign in with Google" or "Sign up with Google" are convenient features that eliminate the need to create new passwords. In many cases, however, they grant more than simple identity verification: they authorize external tools to read and write corporate Gmail, Drive, Calendar, and more. In this article, we explain how organizations can regain control over access permissions granted to external tools without management's awareness.
What gets shared behind "Sign in with Google"
When logging into an external tool using a Google account, a consent screen appears stating, "This app wants to access your Google Account." Many employees click "Allow" without reading the details. The permissions granted vary widely by tool: while some only request basic email addresses and names, others ask for extensive control, such as reading all Gmail messages, accessing all files in Google Drive, or editing Calendar schedules.
The problem is that this authorization is not a one-time event; it remains active until the employee revokes it. Even if the employee stops using the tool or leaves the company, access persists. As highlighted in the opening consultation, it is common for obscure, forgotten tools to retain continuous access to company emails. While our article on generative AI usage guidelines addressed how far AI tools introduced by well-meaning employees can extract corporate data, external app integrations serve as the technical gateway for those risks.
Administrators can review "who granted what access to which app" after the fact
What many executives and IT administrators do not realize is that Google Workspace administrators can review a consolidated list showing which employees granted what permissions to which third-party apps. Opening "App access control" in the Admin console displays all external applications connected by employees, the permissions they request (such as Gmail or Drive), and the number of active users.
Therefore, the first step is not purchasing a new security tool, but auditing what is currently connected. Just as auditing Google Drive sharing settings was covered in our article on auditing shared files, external app integrations require the same approach: start by making hidden access permissions visible. Reviewing this list almost always reveals several unfamiliar tools.
Block, Trust, or Limit scope: how strictly should you restrict access?
Once your audit is complete, determine how to handle each application. In Google Workspace, external application statuses can be managed primarily under the following categories.
| Status | Meaning |
|---|---|
| Trusted | Apps approved by the organization; employees can integrate them without restrictions |
| Block | Apps blocked from accessing corporate data; connection attempts are halted |
| Restricted | Default behavior applied to unconfigured apps (e.g., automatically blocking access to sensitive data like Gmail and Drive) |
The core decision lies in how to treat unknown, unclassified apps by default. Setting the default to "Restricted" ensures that whenever an employee attempts to grant a new tool access to corporate Drive or Gmail, the connection is paused and routed to an administrator approval queue. Administrators can then approve only business-critical apps while leaving the rest unapproved (denied). At the end of 2024, granular controls allowing administrators to restrict permissions to specific API scopes per app became generally available, providing even tighter administrative governance.
Overly strict policies cause internal friction when employees complain about being unable to use necessary tools, so establishing practical boundaries tailored to actual workflow needs is essential. While restricting access based on context and criteria was covered in our article on contextual access restrictions, governing external apps is likewise an architectural task of balancing convenience and protection tailored to your business.
Retaining organizational control over third-party tool gateways
Employees proactively discovering and utilizing great productivity tools is positive for business efficiency. What is dangerous is when those gateways exist outside corporate oversight, leaving no one aware of who authorized what. By maintaining administrative visibility over what corporate emails and files connect to via "Sign in with Google" and blocking unknown apps by default, you substantially minimize data leak risks stemming from former employees or unvetted tools.
"We want an audit of what third-party tools our employees have connected to corporate data," "We want to block risky apps while ensuring business-critical tools run smoothly," or "We need to establish generative AI policies alongside technical access controls"—if you need assistance with these challenges, feel free to contact GleamHub's Google Workspace operational support. We will help bring third-party gateways under administrative control without sacrificing team productivity.
