Suspicious Defender Exclusion Added via Set-MpPreference

ATT&CK techniques

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects use of Set-MpPreference with an exclusion path parameter to exempt a directory from Windows Defender scanning, a defense-evasion step performed by the PureCrypter loader. Adding broad exclusions is rarely a legitimate interactive action.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious ESXi Firewall Disable via esxcli (via process_creation)

Malicious ESXi Syslog Redirection to tmp via esxcli

Suspicious Windows Defender Exclusion Enumeration via reg query (via process_creation)

Malicious Windows Defender Exclusion Added via PowerShell (via process_creation)

Malicious BYOVD EDR Kill via Renamed GMER Driver by Agonizing Serpens

Suspicious Defender Exclusion Added via Set-MpPreference

Pivot detection · T1685 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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