Detection: PowerShell PInvoke Process Injection API Chain

Updated Date: 2026-04-22 ID: 3f1a2b4c-d5e6-7890-abcd-ef1234567890 Author: Teoderick Contreras, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects PowerShell Script Block Logging (Event ID 4104) evidence of a complete P/Invoke process-injection API chain at either the compile phase or the execution phase. Portions of this search were modified to retain the same functionality while preventing antivirus products from alerting on the detection itself

Search

 1`powershell`
 2EventCode=4104
 3ScriptBlockText="*add-type*"
 4ScriptBlockText="*DllImport*"
 5ScriptBlockText IN (
 6    "*extern IntPtr*",
 7    "*extern bool*",
 8    "*extern uint*",
 9    "*extern int*"
10)
11
12| where
13    (
14        match(ScriptBlockText, "(?i)[v][i][r][t][u][a][l][a][l][l][o][c]")
15        AND match(ScriptBlockText, "(?i)[v][i][r][t][u][a][l][p][r][o][t][e][c][t]")
16        AND match(ScriptBlockText, "(?i)[c][r][e][a][t][e][t][h][r][e][a][d]")
17    )
18    OR
19    (
20        match(ScriptBlockText, "(?i)[o][p][e][n][p][r][o][c][e][s][s]")
21        AND match(ScriptBlockText, "(?i)[v][i][r][t][u][a][l][a][l][l][o][c]")
22        AND match(ScriptBlockText, "(?i)[w][r][i][t][e][p][r][o][c][e][s][s][m][e][m][o][r][y]")
23        AND (
24            match(ScriptBlockText, "(?i)[c][r][e][a][t][e][r][e][m][o][t][e][t][h][r][e][a][d]")
25            OR
26            match(ScriptBlockText, "(?i)[q][u][e][u][e][u][s][e][r][a][p][c]")
27        )
28    )
29    OR
30    (
31        match(ScriptBlockText, "(?i)[o][p][e][n][t][h][r][e][a][d]")
32        AND match(ScriptBlockText, "(?i)[s][u][s][p][e][n][d][t][h][r][e][a][d]")
33        AND match(ScriptBlockText, "(?i)[g][e][t][t][h][r][e][a][d][c][o][n][t][e][x][t]")
34        AND match(ScriptBlockText, "(?i)[w][r][i][t][e][p][r][o][c][e][s][s][m][e][m][o][r][y]")
35        AND match(ScriptBlockText, "(?i)[s][e][t][t][h][r][e][a][d][c][o][n][t][e][x][t]")
36        AND match(ScriptBlockText, "(?i)[r][e][s][u][m][e][t][h][r][e][a][d]")
37    )
38    OR
39    (
40        match(ScriptBlockText, "(?i)[c][r][e][a][t][e][p][r][o][c][e][s][s]")
41        AND match(ScriptBlockText, "(?i)[v][i][r][t][u][a][l][a][l][l][o][c]")
42        AND match(ScriptBlockText, "(?i)[w][r][i][t][e][p][r][o][c][e][s][s][m][e][m][o][r][y]")
43        AND match(ScriptBlockText, "(?i)[s][e][t][t][h][r][e][a][d][c][o][n][t][e][x][t]")
44        AND ScriptBlockText = "*ResumeThread*"
45    )
46    OR
47    (
48        match(ScriptBlockText, "(?i)[n][t][c][r][e][a][t][e][s][e][c][t][i][o][n]")
49        AND match(ScriptBlockText, "(?i)[n][t][m][a][p][v][i][e][w][o][f][s][e][c][t][i][o][n]")
50        AND match(ScriptBlockText, "(?i)[c][r][e][a][t][e][r][e][m][o][t][e][t][h][r][e][a][d]")
51    )
52
53| fillnull
54
55| stats count min(_time) as firstTime
56              max(_time) as lastTime
57   by dest signature signature_id user_id vendor_product EventID
58      Guid Opcode Name Path ProcessID ScriptBlockId ScriptBlockText
59
60| `security_content_ctime(firstTime)`
61
62| `security_content_ctime(lastTime)`
63
64| `powershell_pinvoke_process_injection_api_chain_filter`

Data Source

Name	Platform	Sourcetype	Source
Powershell Script Block Logging 4104	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Microsoft-Windows-PowerShell/Operational'`

Macros Used

Name	Value
powershell	`(source=WinEventLog:Microsoft-Windows-PowerShell/Operational OR source="XmlWinEventLog:Microsoft-Windows-PowerShell/Operational" OR source=WinEventLog:PowerShellCore/Operational OR source="XmlWinEventLog:PowerShellCore/Operational")`
powershell_pinvoke_process_injection_api_chain_filter	`search *`

powershell_pinvoke_process_injection_api_chain_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1055.001	Dynamic-link Library Injection	Privilege Escalation
T1055.003	Thread Execution Hijacking	Stealth
T1055.004	Asynchronous Procedure Call	Privilege Escalation
T1055.012	Process Hollowing	Stealth
T1055.013	Process Doppelgänging	Privilege Escalation
T1059.001	PowerShell	Stealth
T1620	Reflective Code Loading	Privilege Escalation

Exploitation

Installation

DE.CM

CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Notable	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Risk Event	True

This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

The following analytic requires PowerShell operational logs to be imported. Modify the powershell macro as needed to match the sourcetype or add index. This analytic is specific to 4104, or PowerShell Script Block Logging.

Known False Positives

No false positives have been identified at this time.

Associated Analytic Story

VIP Keylogger

Risk Based Analytics (RBA)

Risk Message:

A PowerShell script Script block ID [$ScriptBlockId$] contains a possible P-Invoke process injection API chain via either inline Add-Type class declaration or direct static method invocation on [$dest$]

Risk Object	Risk Object Type	Risk Score	Threat Objects
user_id	user	50	No Threat Objects
dest	system	50	No Threat Objects

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-PowerShell/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-PowerShell/Operational`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 1