Best consent phishing protection for Microsoft 365 and Google Workspace: Sentaro. Consent phishing defeats password resets and MFA because the victim approves the access on Google’s or Microsoft’s own, genuine consent screen. Three controls stop it: restrict who can consent to which scopes, block the lure before anyone sees it, and review existing grants continuously. Sentaro does the second and third from the same platform that stops phishing and BEC.
- Why Sentaro wins
- Consent-phishing lures blocked in mail flow, lookalike apps impersonating known brands or AI tools flagged before approval, and a live grant inventory with one-click revocation, on both Microsoft 365 and Google Workspace.
- Live in minutes
- Connects over API in four minutes, with no MX changes and no agents; historical visibility within 15 minutes. $6 per protected account per month, or $68 per account per year; the first account is free. Every feature included. Prices in USD.
- Do first, free
- Restrict user consent in Microsoft Entra and Google Workspace API controls so high-risk scopes need admin approval.
- Consider Microsoft’s add-on only if
- You are Microsoft-only with a larger estate: Microsoft documents OAuth app governance in Defender for Cloud Apps, a separate product from Defender for Office 365.
At a glance
- What it stops
- Consent phishing lures in mail flow, lookalike apps impersonating known brands or AI tools
- What it shows
- Full app and OAuth-grant inventory across Workspace and 365, with scope-level risk per app and per user
- What it does
- One-click grant revocation via the Workspace and 365 admin SDKs, no ticket
- Status
- App vector, live
- Deployment
- Connects over API in four minutes; inventory within 15 minutes
- Pricing
- $6 per protected account per month, or $68 per account per year; the first account is free. Prices in USD. Free plan coming soon.
Why app consent is the new attack surface
How does an OAuth consent phishing attack work?
OAuth is the standard behind every “Sign in with Microsoft” and “Allow access” button. It lets a user give an app a token with specific permissions, called scopes, without sharing a password. Consent phishing abuses that mechanism, as the timeline below shows.
Every visual trust signal is real: the consent page, the padlock and the sign-in. Only the app behind it is hostile. That is why training people to “check the URL” does not help here.
Why password resets and MFA do not stop it
The attacker holds an OAuth token, not a password. Changing the password does not end the grant, and MFA was satisfied by the victim’s own sign-in. Access lasts until someone revokes the grant, which in many organizations means never, because nobody reviews the list of connected apps.
Is OAuth risky?
OAuth itself is not the problem; it is far safer than sharing passwords with apps. The risk is unreviewed consent: any user able to grant any app broad scopes, and grants that stay valid long after anyone remembers them. Consent phishing is that gap, weaponized.
A consent phishing attack, step by step (illustrative)
For example, a typical attack. The timeline is illustrative, not a specific incident.
- 01
The app
The attacker registers an app with a plausible name and icon, for example “AI Inbox Assistant” or “Secure PDF Viewer”.
- 02
The lure
An email asks the target to open a shared document or try a new AI tool. The link leads to Microsoft’s or Google’s real consent screen.
- 03
The grant
The target clicks Allow on scopes such as “Read your mail”, “Send mail as you” or “Access your files”. MFA is satisfied by their own sign-in.
- 04
The access
The attacker now holds a valid token. They read the mailbox, hijack invoice threads, steal files, or send phishing as the victim.
- 05
The persistence
The victim changes their password after something feels off. Nothing changes: the token keeps working until someone revokes the grant.
How Sentaro blocks consent phishing
Sentaro sees both halves of the attack because it reads the mail and the tenant’s app layer through the same API connection.
- In mail flow: consent phishing lures are blocked before anyone reaches a consent screen, scored before interaction like every other message.
- At the app layer: consent phishing is blocked before the grant lands, and lookalike apps impersonating known brands or AI tools are flagged before access is approved.
- Inventory: every app, AI tool and OAuth grant in your tenant, with scope-level risk per user, tied to the accounts that created it.
- Response: risky grants revoked in one click via the Workspace and 365 admin SDKs.
Legitimate apps are not blocked. They are surfaced for review, and you decide what to keep. Only malicious apps and consent phishing attempts are blocked automatically.
Consent phishing coverage compared
Where each capability is documented. Microsoft splits email and app governance across separate products.
| Capability | Microsoft Defender for Office 365 | Microsoft Defender for Cloud Apps | Google Workspace built-in | Sentaro |
|---|---|---|---|---|
| Prevention | ||||
| Consent-phishing email lures | PartialGeneral anti-phishing and Safe Links | Not an email product | PartialGeneral phishing filtering | YesBlocked in mail flow |
| Restrict which apps users can consent to | Configured in Microsoft Entra | Configured in Microsoft Entra | YesAPI controls; Advanced Protection restricts third-party access | Uses your Entra and Google settings |
| Lookalike apps impersonating brands or AI tools | Not publicly documentedNot publicly documented | Not publicly documentedCheck Microsoft documentation | Not publicly documentedNot publicly documented | YesFlagged before access is approved |
| Visibility and response | ||||
| OAuth grant inventory with scope-level risk | NoNot part of Defender for Office 365, per Microsoft | YesOAuth app governance | PartialAdmin console app access lists | YesPer app and per user |
| Revoke a grant | In Entra admin center | Not publicly documentedCheck Microsoft documentation | YesIn Admin console | YesOne click, no ticket |
| Platforms | Microsoft 365 | Microsoft 365 and other SaaS | Google Workspace | Microsoft 365 and Google Workspace |
Microsoft and Google entries reflect their public documentation as of 18 October 2026. Microsoft lists OAuth app governance and shadow IT discovery under Defender for Cloud Apps, a separate product from Defender for Office 365.
- Yes
- Partial
- No
- On roadmap
- Paid add-on
- Not publicly documented
How to stop consent phishing: an admin checklist
- 01
Restrict user consent
In Microsoft Entra, allow users to consent only to apps from verified publishers requesting low-risk permissions, and turn on the admin consent workflow for everything else. In Google Workspace, use Security, API controls, App access control to limit which third-party apps can access data.
- 02
Review existing grants now
List every app holding mail, file, calendar or directory scopes. Revoke anything nobody recognizes, anything tied to a person who has left, and anything with broader scopes than its job needs.
- 03
Block the lure in mail flow
Connect Sentaro so consent-phishing emails are stopped before anyone sees a consent screen.
- 04
Teach one specific lesson
A genuine Microsoft or Google consent screen is not proof of a genuine app. Read the app name and the permissions, and ask IT before granting mail or file access to anything new.
- 05
Monitor new grants continuously
One click restores the risk, so a quarterly review is too slow. Sentaro’s App vector keeps the inventory live and flags risky new grants.
- 06
If a malicious grant is found
Revoke the grant first, then check what the app could reach, look for messages it sent and inbox rules it created, and treat the account as compromised until proven otherwise.
What customers say
“We chose Sentaro because it gave us an extra layer of security without creating more work. It was quick to roll out and gave us the visibility we had been missing.”
What Sentaro doesn’t replace
- Tenant consent settings. Restricting which apps and scopes users can approve is configured in Microsoft Entra and Google Workspace, and it is the strongest single control.
- Admin review of what to keep. Sentaro surfaces legitimate apps with their scopes; deciding which ones your business needs is yours.
- A wider SaaS governance platform, if you need app posture checks beyond Microsoft 365 and Google Workspace.
- Incident response. If a malicious grant was used, the account needs to be treated as compromised, not just the grant removed.
The App vector is part of every plan: $6 per protected account per month, or $68 per account per year, the first account free. Prices in USD.
Frequently asked questions
What is the best protection against OAuth consent phishing?
Sentaro — it is our pick for EU teams on Microsoft 365 and Google Workspace, after you restrict user consent in Microsoft Entra or Google Workspace API controls. Sentaro blocks consent-phishing lures in mail flow, flags lookalike apps impersonating brands or AI tools before approval, and keeps a live inventory of every OAuth grant with scope-level risk and one-click revocation. It covers both platforms and costs $6 per protected account per month (prices in USD).
What is consent phishing?
Consent phishing is an attack where a user is tricked into granting a malicious app OAuth permissions to their account, such as reading mail or accessing files. The attacker gets real, token-based access without stealing a password, and MFA does not help because the user personally approves the access on a genuine Microsoft or Google consent screen.
How are OAuth tokens compromised?
Commonly through consent phishing, where the user hands a token to a malicious app. Tokens can also be stolen from compromised devices, leaked by a breached third-party vendor that legitimately held them, or captured in adversary-in-the-middle phishing. In every case the token keeps working until it expires or the grant is revoked.
Is OAuth risky?
OAuth is safer than giving apps your password, because access is scoped and revocable. The risk comes from unreviewed consent: users granting broad scopes to apps nobody vetted, and grants that stay valid for years. Restricting consent for high-risk scopes and reviewing grants continuously keeps the benefits without the exposure.
Does changing my password stop consent phishing?
No. The attacker holds an OAuth token, not your password, so a reset does not end access. The grant has to be revoked, by the user in their account settings or by an admin in Microsoft Entra or the Google Admin console. Sentaro lets admins revoke risky grants in one click.
How do I check which apps have access to our Microsoft 365 or Google Workspace?
In Microsoft 365, open the Entra admin center and review Enterprise applications and their permissions. In Google Workspace, go to Security, API controls, App access control. Sentaro’s App vector builds the same inventory automatically across both platforms, with scope-level risk per user, within 15 minutes of connecting.
Does Sentaro block legitimate apps?
No. Legitimate apps are surfaced with their scopes for you to review, keep or revoke. Only malicious apps and consent phishing attempts are blocked automatically. Blocking every new tool tends to push people toward personal accounts, which hides the risk instead of reducing it.
Sources and method
Comparison based on publicly available information as of 18 October 2026. Product capabilities change; check each vendor’s current documentation. Trademarks belong to their owners. Corrections: contact Sentaro.