ORCA.205: Common attachment type filter is enabled.
| ID | ORCA.205 |
| Severity | Medium |
| Suite | ORCA |
| Product | Defender |
| Related products | Exchange Online |
| Feature | Anti-malware |
| Security area | Email and collaboration protection |
| Resource type | Policy |
| User impact of fixing | Low |
| Effort to fix | Low |
| Framework controls | nist-800-53-r5:SI-3 Malicious Code Protection |
| MITRE ATT&CK | T1566.001, T1204.002 |
| Reads from | Exchange Online |
What this checks and how to fix it
Section titled “What this checks and how to fix it”The common attachment type filter can block file types that commonly contain malware, including in internal emails.
Remediation action
Section titled “Remediation action”Enable common attachment type filter.
Related Links
Section titled “Related Links”- Configure anti-malware policies
- Microsoft 365 Defender Portal - Anti-malware
- 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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