Chopper Webshell Process Pattern
Detects patterns found in process executions cause by China Chopper like tiny (ASPX) webshells
Sigma rule (View on GitHub)
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
References
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