ORCA.118.3: Your own domains are not being allow listed in an unsafe manner in Anti-Spam Policies.
| ID | ORCA.118.3 |
| Severity | High |
| Suite | ORCA |
| Product | Defender |
| Related products | Exchange Online |
| Feature | Anti-spam |
| 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, T1684.002 |
| Reads from | Exchange Online |
What this checks and how to fix it
Section titled “What this checks and how to fix it”Emails coming from allow listed domains bypass several layers of protection within Exchange Online Protection. When allow listing your own domains, an attacker can spoof any account in your organisation that has this domain. This is a significant phishing attack vector.
Remediation action
Section titled “Remediation action”Remove allow listing on domains belonging to your organisation.
Related Links
Section titled “Related Links”Mito check, based on ORCA. Author: thomas-s-schmidt. 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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