Potentially Suspicious CMD Shell Output Redirect

 1title: Potentially Suspicious CMD Shell Output Redirect
 2id: 8e0bb260-d4b2-4fff-bb8d-3f82118e6892
 3related:
 4    - id: aa2efee7-34dd-446e-8a37-40790a66efd7
 5      type: derived
 6    - id: 4f4eaa9f-5ad4-410c-a4be-bc6132b0175a
 7      type: similar
 8status: experimental
 9description: |
10    Detects inline Windows shell commands redirecting output via the ">" symbol to a suspicious location.
11    This technique is sometimes used by malicious actors in order to redirect the output of reconnaissance commands such as "hostname" and "dir" to files for future exfiltration.    
12references:
13    - https://thedfirreport.com/2022/07/11/select-xmrig-from-sqlserver/
14author: Nasreddine Bencherchali (Nextron Systems)
15date: 2022-07-12
16modified: 2024-03-19
17tags:
18    - attack.defense-evasion
19    - attack.t1218
20logsource:
21    category: process_creation
22    product: windows
23detection:
24    selection_img:
25        - Image|endswith: '\cmd.exe'
26        - OriginalFileName: 'Cmd.Exe'
27    selection_cli_1:
28        CommandLine|contains:
29            # Note: Add more suspicious locations as you find them
30            # Note: The space from the start is missing to cover append operations ">>"
31            # Note: We use the "?" to account for both a single and a double quote
32            # Note: If you want to account for more spaces which is still a valid bypass option. Use a regex with "\s"
33            - '>?%APPDATA%\'
34            - '>?%TEMP%\'
35            - '>?%TMP%\'
36            - '>?%USERPROFILE%\'
37            - '>?C:\ProgramData\'
38            - '>?C:\Temp\'
39            - '>?C:\Users\Public\'
40            - '>?C:\Windows\Temp\'
41    selection_cli_2:
42        CommandLine|contains:
43            - ' >'
44            - '">'
45            - "'>"
46        CommandLine|contains|all:
47            - 'C:\Users\'
48            - '\AppData\Local\'
49    condition: selection_img and 1 of selection_cli_*
50falsepositives:
51    - Legitimate admin or third party scripts used for diagnostic collection might generate some false positives
52level: medium