# Internal Sender notifications are disabled

Notifying internal senders about malware detected in email messages could have negative impact.

Source: https://maester.dev/docs/tests/ORCA.110

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<div class="test-byline"><div class="test-byline-avatars"><a class="test-byline-avatar test-byline-avatar--author" href="/contributors/soulemike" title="Michael Soule · Original author"><img src="https://github.com/soulemike.png" alt="Michael Soule" width="28" height="28" loading="lazy" decoding="async" /></a></div><div class="test-byline-meta"><span class="test-byline-text">Contributed by <a href="/contributors/soulemike">Michael Soule</a></span><a class="test-byline-link" href="/contributors">All contributors →</a></div></div>

<p class="test-part">Part of <a href="/docs/tests/orca">ORCA</a> · Defender · Anti-malware · <a href="/docs/tests">All checks</a></p>

```powershell title="Run this check"
Invoke-Maester -TestId ORCA.110
```

## Overview

Notifying internal senders about malware detected in email messages could have negative impact. An adversary with access to an already compromised mailbox may use this information to verify effectiveness of malware detection.

#### Remediation action

Disable notifying internal senders of malware detection.

#### Related Links

* [Microsoft 365 Defender Portal - Anti-malware](https://security.microsoft.com/antimalwarev2)
* [Recommended settings for EOP and Office 365 Microsoft Defender for Office 365 security](https://aka.ms/orca-atpp-docs-6)

## Details

<details>
<summary>Every attribute of this check</summary>

| Field | Value |
| --- | --- |
| Test ID | ORCA.110 |
| Severity | Low |
| Suite | ORCA |
| Product | Defender |
| Related products | Exchange Online |
| Feature | Anti-malware |
| Area | Email and collaboration protection |
| Resource type | Policy |
| User impact | Low |
| Implementation cost | Low |
| MITRE ATT&CK | None |
| PowerShell test | [Test-ORCA110](https://github.com/maester365/maester/blob/main/tests/orca/Test.ORCA.110.ps1) |
| Services | ExchangeOnline |

</details>

## Source

- Test: [`tests/orca/Test.ORCA.110.ps1`](https://github.com/maester365/maester/blob/main/tests/orca/Test.ORCA.110.ps1)
- Documentation: [`tests/orca/Test.ORCA.110.md`](https://github.com/maester365/maester/blob/main/tests/orca/Test.ORCA.110.md)
