Potential DLL Side-Loading via Microsoft Antimalware Service Executable
editPotential DLL Side-Loading via Microsoft Antimalware Service Executable
editIdentifies a Windows trusted program that is known to be vulnerable to DLL Search Order Hijacking starting after being renamed or from a non-standard path. This is uncommon behavior and may indicate an attempt to evade defenses via side-loading a malicious DLL within the memory space of one of those processes.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
- logs-windows.*
Severity: high
Risk score: 73
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Defense Evasion
Version: 100 (version history)
Added (Elastic Stack release): 7.14.0
Last modified (Elastic Stack release): 8.5.0
Rule authors: Elastic, Dennis Perto
Rule license: Elastic License v2
Potential false positives
editMicrosoft Antimalware Service Executable installed on non default installation path.
Investigation guide
editRule query
editprocess where event.type == "start" and (process.pe.original_file_name == "MsMpEng.exe" and not process.name : "MsMpEng.exe") or (process.name : "MsMpEng.exe" and not process.executable : ("?:\\ProgramData\\Microsoft\\Windows Defender\\*.exe", "?:\\Program Files\\Windows Defender\\*.exe", "?:\\Program Files (x86)\\Windows Defender\\*.exe", "?:\\Program Files\\Microsoft Security Client\\*.exe", "?:\\Program Files (x86)\\Microsoft Security Client\\*.exe"))
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Hijack Execution Flow
- ID: T1574
- Reference URL: https://attack.mitre.org/techniques/T1574/
Rule version history
edit- Version 100 (8.5.0 release)
-
- Formatting only
- Version 5 (8.4.0 release)
-
- Formatting only
- Version 3 (8.2.0 release)
-
- Formatting only
- Version 2 (7.16.0 release)
-
-
Updated query, changed from:
process where event.type == "start" and (process.pe.original_file_name == "MsMpEng.exe" and not process.name : "MsMpEng.exe") or (process.name : "MsMpEng.exe" and not process.executable : ("?:\\ProgramData\\Microsoft\\Windows Defender\\*.exe", "?:\\Program Files\\Windows Defender\\*.exe", "?:\\Program Files (x86)\\Windows Defender\\*.exe"))
-