ORCA.124: Safe attachments unknown malware response set to block messages.
| ID | ORCA.124 |
| Severity | High |
| Suite | ORCA |
| Product | Defender |
| Related products | Exchange Online |
| Feature | Safe Attachments |
| 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 |
| Licence needed | ATP_ENTERPRISE |
What this checks and how to fix it
Section titled “What this checks and how to fix it”When Safe attachments unknown malware response set to block, Microsoft Defender for Office 365 prevents current and future messages with detected malware from proceeding and sends messages to quarantine in Office 365.
Remediation action
Section titled “Remediation action”Set Safe attachments unknown malware response to block messages.
Related Links
Section titled “Related Links”- Microsoft 365 Defender Portal - Safe attachments
- Recommended settings for EOP and Microsoft Defender for Office 365 security
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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