Disable AMSI Through Registry
The following analytic detects modifications to the Windows registry that disable the Antimalware Scan Interface (AMSI) by setting the "AmsiEnable" value to "0x00000000". This detection leverages data from the…
Description
The following analytic detects modifications to the Windows registry that disable the Antimalware Scan Interface (AMSI) by setting the "AmsiEnable" value to "0x00000000". This detection leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path "*\\SOFTWARE\\Microsoft\\Windows Script\\Settings\\AmsiEnable". Disabling AMSI is significant as it is a common technique used by ransomware, Remote Access Trojans (RATs), and Advanced Persistent Threats (APTs) to evade detection and impair defenses. If confirmed malicious, this activity could allow attackers to execute payloads with minimal alerts, leading to potential system compromise and data exfiltration.
Detection logic
Detection requirements
- Platform
- ContainersESXiIaaSLinuxmacOSNetwork DevicesWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- sysmon_eventid_13
Known benign triggers
- network operator may disable this feature of windows but not so common.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| blog.f-secure.com/hunting-for-amsi-bypasses/ | Only this detection cites it |
| gist.github.com/rxwx/8955e5abf18dc258fd6b43a3a7f4dbf9 | Only this detection cites it |
From the source
- At source
- Open at source
- Upstream identifier
- 9c27ec42-d338-11eb-9044-acde48001122
- Tagged by the source as
- CISA AA23-347ARansomwareWindows Registry AbuseEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1