ORCA.229: No trusted domains in Anti-phishing policy.
| ID | ORCA.229 |
| Severity | Medium |
| Suite | ORCA |
| Product | Defender |
| Related products | Exchange Online |
| Feature | Anti-phishing |
| Security area | Email and collaboration protection |
| Resource type | Policy |
| User impact of fixing | Low |
| Effort to fix | Medium |
| Framework controls | nist-800-53-r5:SI-8 Spam Protection |
| MITRE ATT&CK | T1566, T1684.001 |
| Reads from | Exchange Online |
| Licence needed | ATP_ENTERPRISE |
What this checks and how to fix it
Section titled “What this checks and how to fix it”Adding domains as trusted in Anti-phishing policy will result in the action for protected domains, protected users or mailbox intelligence protection will be not applied to messages coming from these sender domains. If a trusted domain needs to be added based on organizational requirements it should be reviewed regularly and updated as needed. We also do not recommend adding domains from shared services.
Remediation action
Section titled “Remediation action”Remove allow listing on domains in Anti-phishing policy.
Related Links
Section titled “Related Links”- Microsoft 365 Defender Portal - Anti-phishing
- Recommended settings for EOP and Microsoft Defender for Office 365
Mito check, based on ORCA. Author: soulemike. Open-source licences.
Open-source licences. CIS Benchmark material © Center for Internet Security, Inc.; CISA SCuBA baselines are public domain (CC0).
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