Dynamic .NET Compilation Via Csc.EXE - Hunting

testmedium
Log-Quelle: windows · process_creationAutor Nasreddine Bencherchali (Nextron Systems)Datum 2023-08-02
01

Beschreibung

Was dies ist, in Kürze.

Detects execution of "csc.exe" to compile .NET code. Attackers often leverage this to compile code on the fly and use it in other stages.

02

Tags

attack.stealthattack.t1027.004detection.threat-hunting
03

Regelquelle (YAML)

title: Dynamic .NET Compilation Via Csc.EXE - Hunting
id: acf2807c-805b-4042-aab9-f86b6ba9cb2b
related:
    - id: dcaa3f04-70c3-427a-80b4-b870d73c94c4
      type: derived
status: test
description: Detects execution of "csc.exe" to compile .NET code. Attackers often leverage this to compile code on the fly and use it in other stages.
references:
    - https://securityboulevard.com/2019/08/agent-tesla-evading-edr-by-removing-api-hooks/
    - https://www.clearskysec.com/wp-content/uploads/2018/11/MuddyWater-Operations-in-Lebanon-and-Oman.pdf
    - https://app.any.run/tasks/c6993447-d1d8-414e-b856-675325e5aa09/
    - https://twitter.com/gN3mes1s/status/1206874118282448897
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-08-02
tags:
    - attack.stealth
    - attack.t1027.004
    - detection.threat-hunting
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\csc.exe'
        CommandLine|contains: '/noconfig /fullpaths @'
    condition: selection
falsepositives:
    - Many legitimate applications make use of dynamic compilation. Use this rule to hunt for anomalies
level: medium
regression_tests_path: regression_data/rules-threat-hunting/windows/process_creation/proc_creation_win_csc_compilation/info.yml
04

erkennt Techniken (1)

ATT&CK-Techniken, die dies ermöglicht oder abbildet.

05

Referenzen

Externe Belege — Patches, Meldungen, Analysen.