Elastic Security Detection Rules

Suspicious .NET Code Compilation

Last updated 10 days ago on 2025-02-21
Created 5 years ago on 2020-08-21

About

Identifies executions of .NET compilers with suspicious parent processes, which can indicate an attacker's attempt to compile code after delivery in order to bypass security mechanisms.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: Defense EvasionTactic: ExecutionData Source: Elastic EndgameData Source: Elastic DefendData Source: Windows Security Event LogsData Source: Microsoft Defender for EndpointData Source: SysmonData Source: SentinelOneData Source: CrowdstrikeLanguage: eql
Severity
medium
Risk Score
47
MITRE ATT&CK™

Defense Evasion (TA0005)(opens in a new tab or window)

↳ Obfuscated Files or Information (T1027)(opens in a new tab or window)

Execution (TA0002)(opens in a new tab or window)

↳ Command and Scripting Interpreter (T1059)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
endgame-*logs-crowdstrike.fdr*logs-endpoint.events.process-*logs-m365_defender.event-*logs-sentinel_one_cloud_funnel.*logs-system.security*logs-windows.forwarded*logs-windows.sysmon_operational-*winlogbeat-*
Related Integrations

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

system(opens in a new tab or window)

m365_defender(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

Query
process where host.os.type == "windows" and event.type == "start" and
  process.name : ("csc.exe", "vbc.exe") and
  process.parent.name : ("wscript.exe", "mshta.exe", "cscript.exe", "wmic.exe", "svchost.exe", "rundll32.exe", "cmstp.exe", "regsvr32.exe")

Install detection rules in Elastic Security

Detect Suspicious .NET Code Compilation in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).