Best Slack and Teams phishing protection for teams already protecting email: Sentaro. Attackers also work in chat: an external Teams message from “the help desk” carries none of the mail-flow signals an email filter looks for. Sentaro lists Email, Slack and Teams as its channels and says the same engine scores all three. Its public material describes email coverage in far more detail than chat, so confirm the Slack and Teams depth on a demo with your own workspace before you rely on it.
- Why Sentaro wins
- One engine reading intent across email, Slack and Teams, in the same console and price as your email protection; OAuth apps connected to the tenant inventoried in the App vector; API connection in four minutes; hosted in Sweden on Microsoft Azure.
- Already covered by Microsoft
- Microsoft documents that Defender for Office 365 Plan 1 adds Safe Links in Teams, Safe Attachments for files in SharePoint, OneDrive and Teams, zero-hour auto purge for Teams and quarantine for Teams messages. Switch them on first.
- What to verify
- Which Slack plans and Teams message types are scanned, and which actions are available inside chat. Ask Sentaro directly.
Why chat matters now
What does phishing in Microsoft Teams look like?
Teams phishing is a message request from an external account, usually posing as IT, security or a supplier, that steers the user into approving a sign-in, installing remote-access software or opening a file. It works because chat feels internal and urgent, and because awareness training has mostly focused on email.
Microsoft documented a clear example in August 2023. Midnight Blizzard, the actor the US and UK governments attribute to Russia’s Foreign Intelligence Service, used previously compromised small-business Microsoft 365 tenants, renamed them with security-sounding onmicrosoft.com subdomains, and sent Teams message requests posing as technical support. Targets were asked to enter a code into their Microsoft Authenticator prompt, which handed the attacker a token to their account. Microsoft counted fewer than 40 organizations affected. The lesson Microsoft drew: “any authentication requests not initiated by the user should be treated as malicious.”
And in Slack?
The patterns carry over: for example, a message in a shared channel from a guest posing as a vendor with a “new invoice portal”, or a direct message asking someone to move a conversation to a personal channel. The intent signals are the same as in email: urgency, secrecy, payment or credential requests, and a change of channel. That is why Sentaro runs one engine across all three rather than separate rules per tool.
Teams and Slack coverage: Microsoft vs Sentaro
Microsoft entries come from Microsoft Learn. For Sentaro, “verify” marks details that are not yet in Sentaro’s public documentation.
| Capability | Built-in protection (EOP) | Defender for Office 365 Plan 1 | Defender for Office 365 Plan 2 | Sentaro |
|---|---|---|---|---|
| Microsoft Teams | ||||
| Links in Teams messages | No | YesSafe Links | YesSafe Links | PartialTeams is a live channel for the Message vector; link-handling detail not publicly documented |
| Files shared in Teams | No | YesSafe Attachments for SharePoint, OneDrive and Teams | Yes | Not publicly documentedNot publicly documented |
| Post-delivery removal in Teams | No | YesZAP for Teams, Teams messages in quarantine | YesPlus removing users from chats | Not publicly documentedNot publicly documented |
| User-reported Teams messages | No | Yes | Yes | Not publicly documentedNot publicly documented |
| Hunting across Teams messages | No | No | YesAdvanced hunting | NoNo hunting product |
| Slack | ||||
| Slack message scoring | NoMicrosoft 365 only | No | No | YesListed channel; same engine as email |
| Across channels | ||||
| Intent analysis (payment, credential, secrecy, urgency) | Not publicly documentedNot publicly documented for chat | Not publicly documentedNot publicly documented for chat | Not publicly documentedNot publicly documented for chat | YesCore of the Message vector |
| Google Workspace email in the same console | No | No | No | Yes |
| Price for chat coverage | NoTeams not covered | Included in Plan 1 | Included in Plan 2 | Included in every Sentaro plan |
Sources: Microsoft Learn, mdo-about, accessed 18 October 2026; Sentaro pricing and vector pages.
- Yes
- Partial
- No
- On roadmap
- Paid add-on
- Not publicly documented
What Sentaro documents for Slack and Teams today
We hold this page to the same rule as every Sentaro page: only what Sentaro has published. Here is that list, word for word where it matters.
- The Message vector is “live across email, Slack, Teams”, with “AI scoring on every inbound, before interaction”.
- Its capabilities include “Same engine across email, Slack, and Teams”.
- The pricing page lists “Email, Slack and Teams” as the channels, and every plan includes every feature.
- The platform page lists the integrations as Google Workspace, Microsoft 365, Slack and MS Teams.
What is not yet public: which Slack plans are supported, whether direct messages, shared channels and files are all scanned, which actions (block, quarantine, tag) are available inside Slack and Teams, and whether chat data follows the same retention periods as email in the DPA. Sentaro’s documentation site is still being written. These are fair questions to ask on a demo.
How to reduce phishing risk in Teams and Slack
Tooling is half of it. The other half is configuration that costs nothing.
- Review Teams external access: decide which external domains may chat with your users, rather than allowing all.
- Turn on Defender for Office 365 Plan 1 Teams protections if your licence includes them (Business Premium, and Microsoft 365 or Office 365 E3 from 2026).
- Tell users plainly that IT will never ask them to read out or approve an MFA code in chat. Microsoft’s own guidance: treat any authentication request you did not start as malicious.
- In Slack, restrict who can invite guests and create shared channels, and review installed apps regularly.
- Review the OAuth apps connected to Slack, Teams and your mail tenant. Sentaro’s App vector inventories apps and OAuth grants across Microsoft 365 and Google Workspace.
- Use the same reporting path for chat as for email, so a suspicious Teams message gets the same response as a suspicious email.
What customers report
“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.”
Frequently asked questions
What is the best security for Slack and Microsoft Teams?
Our pick is Sentaro, for teams that want chat and email judged by one engine. Sentaro states the same engine scores email, Slack and Teams, and every channel is included in the $6 per protected account per month price (prices in USD). Turn on Defender for Office 365 Teams protections if you have them, and confirm Sentaro’s chat coverage depth on a demo with your own workspace.
Can you get phished on Microsoft Teams?
Yes. Attackers send Teams message requests from external tenants, often posing as IT support, and ask users to approve a sign-in, share an MFA code or install remote-access tools. Microsoft documented such a campaign by Midnight Blizzard in 2023. Treat any authentication request you did not start as malicious, and restrict external access to domains you trust.
Does Microsoft Defender protect Teams?
Defender for Office 365 Plan 1 does: Safe Links in Teams, Safe Attachments for files in SharePoint, OneDrive and Teams, zero-hour auto purge and quarantine for Teams messages, and user reporting. Plan 2 adds advanced hunting on Teams messages and removing users from chats. The built-in protection that every Microsoft 365 plan includes does not cover Teams.
Does Sentaro protect Slack?
Sentaro lists Slack as one of its three channels, alongside email and Teams, and states that the same engine scores all of them. Which Slack plans, message types and in-app actions are covered is not yet in its public documentation, so confirm the details with Sentaro on a demo.
Does chat protection cost extra with Sentaro?
No. Sentaro’s Pro plan includes every feature, and its pricing page lists Email, Slack and Teams as the channels. Pro costs $6 per protected account per month, or $68 per account per year, and the first account is free. Prices are in USD.
Why use one engine for email and chat?
Because the attack is the same: a believable request that creates urgency, asks for secrecy, or moves money or credentials. An engine that reads intent and relationship context can apply that judgment wherever the message arrives, instead of maintaining separate rules per tool. The Verizon DBIR 2026 reports that 41% of social-engineering breaches involve a non-email channel.
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.