Chopper Webshell Process Pattern

 1title: Chopper Webshell Process Pattern
 2id: fa3c117a-bc0d-416e-a31b-0c0e80653efb
 3status: test
 4description: Detects patterns found in process executions cause by China Chopper like tiny (ASPX) webshells
 5references:
 6    - https://www.microsoft.com/security/blog/2022/09/30/analyzing-attacks-using-the-exchange-vulnerabilities-cve-2022-41040-and-cve-2022-41082/
 7author: Florian Roth (Nextron Systems), MSTI (query)
 8date: 2022/10/01
 9tags:
10    - attack.persistence
11    - attack.t1505.003
12    - attack.t1018
13    - attack.t1033
14    - attack.t1087
15logsource:
16    category: process_creation
17    product: windows
18detection:
19    selection_origin:
20        - Image|endswith: '\w3wp.exe'
21        - ParentImage|endswith: '\w3wp.exe'
22    selection_cmdline:
23        CommandLine|contains:
24            - '&ipconfig&echo'
25            - '&quser&echo'
26            - '&whoami&echo'
27            - '&c:&echo'
28            - '&cd&echo'
29            - '&dir&echo'
30            - '&echo [E]'
31            - '&echo [S]'
32    condition: all of selection_*
33falsepositives:
34    - Unknown
35level: high