Shadow IT discovery for Google Workspace and Microsoft 365
Every SaaS signup, AI tool and OAuth grant announces itself in email. Sentaro's shadow IT discovery tool watches that layer continuously, so you see unsanctioned apps the moment they appear, not at the next audit.
- Discover every new app signup and OAuth grant as it happens
- Surface historical adoption from existing mailbox data
- Block OAuth consent phishing disguised as legitimate apps
- Deploy in minutes via API. No agents, no MX changes, no appliances
Last updated 2026-07-09
Why shadow IT slips past traditional tools
Employees adopt new SaaS and AI tools every week. According to Microsoft research, roughly 80% of employees use non-sanctioned apps to get work done, and organizations typically run far more cloud apps than IT estimates. Free tiers leave no invoice for finance to catch, remote work means adoption never crosses the corporate network, and a single OAuth consent can hand a third party persistent access to mailboxes, calendars and files.
Network-based discovery misses everything adopted off-network. Expense-based discovery misses everything free. Annual audits capture a snapshot that is outdated the same week. Meanwhile, attackers exploit the same blind spot with lookalike apps and OAuth consent phishing. This is why shadow IT and shadow AI keep growing even in organizations that have invested heavily in traditional security stacks.
How Sentaro's shadow IT discovery works
Every tool an employee adopts leaves a trail in the mailbox: a welcome email, a verification link, a receipt, or an OAuth consent against Google Workspace or Microsoft 365. Sentaro's AI Threat Intelligence Agent monitors these signals across its Message, App, Domain and Behavioral Intelligence layers to build a live inventory of what is actually in use, on any device, on any network.
1. Discover every SaaS and AI signup
When employees bypass IT to get work done faster, unsanctioned tools accumulate invisibly: file-sharing services, project tools, and increasingly shadow AI in the form of chatbots, meeting notetakers and AI assistants. Sentaro detects the signup trail these tools create in email (welcome messages, verification links, receipts) and categorizes each discovered app automatically. Because the trail already exists in mailbox data, Sentaro can also surface historical adoption: tools employees signed up for long before you deployed anything, including accounts they have since abandoned but that still hold company data.
2. See and control OAuth grants
The riskiest shadow IT is not an app someone visits; it is an app someone connected. Third-party tools granted mail, drive or calendar scopes on Google Workspace or Microsoft 365 keep that access until it is explicitly revoked, and abandoned grants accumulate for years. Sentaro surfaces every third-party OAuth grant in your environment with its scopes, so overly permissive access is visible, reviewable and revocable before it becomes the quiet backdoor nobody remembers approving.
3. Block consent phishing before access is granted
Discovery alone tells you what already happened. Sentaro also stops the malicious half of the problem: attackers registering lookalike apps, often disguised as popular AI tools, and using OAuth consent phishing to trick employees into granting mailbox access. Because Sentaro already analyzes every message and app signal for phishing and business email compromise, consent phishing attempts are blocked in the same layer, before an employee can click approve. This is the difference between shadow IT inventory tools and shadow IT security: Sentaro does both in one platform.
4. Catch shadow IT risks in employee offboarding
Departing employees keep access to every shadow tool IT never knew about, and the OAuth grants they approved keep working after their account is disabled. Because Sentaro's inventory is built from the email and identity layer, you can review exactly which apps and grants are tied to a departing employee and close them out as part of offboarding, instead of discovering a forgotten account with customer data in it a year later.
How the email layer compares to other discovery methods
| Network / CASB | Expense-based | SaaS mgmt platforms | Sentaro (email layer) | |
|---|---|---|---|---|
| Off-network and remote usage | Missed | Missed | Partial | Detected |
| Free-tier tools (no invoice) | Partial | Missed | Partial | Detected |
| OAuth grants and scopes | No | No | Some | Yes |
| Blocks consent phishing | No | No | No | Yes |
| Historical adoption trail | No | Partial | Partial | Yes, from existing mailbox data |
| Also stops phishing and BEC | No | No | No | Yes |
| Deployment | Appliances or proxies | Finance exports | Multiple integrations | API connection in minutes |
Built for lean IT and security teams
Sentaro is built for teams that run Google Workspace or Microsoft 365 without a 20-person SOC. Discovery is automatic, categorization is automatic, and alerts fire only when something needs a decision. And because shadow IT discovery runs on the same platform that stops phishing and business email compromise, there is no extra tool to buy, deploy or maintain: one API connection covers both.
FAQ
- What is a shadow IT discovery tool?
- A shadow IT discovery tool identifies the software, cloud services and integrations employees use without IT approval. Sentaro does this at the email and identity layer of Google Workspace and Microsoft 365, where every SaaS signup and OAuth grant leaves a trail.
- How is email-based discovery different from a CASB or network monitoring?
- CASBs and network tools only see traffic crossing infrastructure you control. Email-based discovery works regardless of device or network, and catches free-tier signups that never touch a firewall, a proxy or an invoice.
- Can Sentaro find shadow IT that existed before we deployed it?
- Yes. Signup and OAuth trails live in existing mailbox and workspace data, so Sentaro can surface historical adoption, including tools employees signed up for long before deployment.
- Does Sentaro detect shadow AI?
- Yes. AI chatbots, meeting notetakers and OAuth-connected AI assistants are discovered and categorized like any other SaaS, and consent phishing disguised as AI apps is blocked automatically.
- Does Sentaro block employees from using new tools?
- No. Legitimate tools are surfaced for review, and you decide what to allow or revoke. Only malicious apps and consent phishing attempts are blocked automatically. Blocking legitimate productivity tools tends to push usage underground.
- What do I need to deploy it?
- A Google Workspace or Microsoft 365 admin account. Sentaro connects via API in minutes, with no MX record changes, agents or network appliances.
- Can I see which users are behind each discovered app?
- Yes. Each discovered app and OAuth grant is tied to the accounts that created it, so you can see who adopted what, and follow up with the right people instead of sending company-wide warnings.
- How is this priced?
- Shadow IT discovery is part of the Sentaro platform, not a separate module. See the pricing page for current plans.
See what's hiding in your environment
Connect Sentaro to Google Workspace or Microsoft 365 and get a live inventory of every app, AI tool and OAuth grant in your email environment, typically within the first hour.