The following analytic identifies the Windows InstallUtil.exe binary loading
vaultcli.dll and Samlib.dll
. This technique may be used to execute code to bypassing application control and capture credentials by utilizing a tool like MimiKatz. \
is used in a malicous manner, the path to an executable on the filesystem is typically specified. Take note of the parent process. In a suspicious instance, this will be spawned from a non-standard process like Cmd.exe
If used by a developer, typically this will be found with multiple command-line switches/arguments and spawn from Visual Studio.
During triage review resulting network connections, file modifications, and parallel processes. Capture any artifacts and review further.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-06-01
- Author: Michael Haag, Mauricio Velazo, Splunk
- ID: ccfeddec-43ec-11ec-b494-acde48001122
Kill Chain Phase
1 2 3 4 5 6 `sysmon` EventCode=7 process_name=installutil.exe ImageLoaded IN ("*\\samlib.dll", "*\\vaultcli.dll") | stats count min(_time) as firstTime max(_time) as lastTime by Computer, process_name, ImageLoaded, OriginalFileName, ProcessId | rename Computer as dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_installutil_credential_theft_filter`
The SPL above uses the following Macros:
windows_installutil_credential_theft_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
How To Implement
To successfully implement this search, you need to be ingesting logs with the process name, parent process, and module loads from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.
Known False Positives
Typically this will not trigger as by it's very nature InstallUtil does not need credentials. Filter as needed.
Associated Analytic Story
|80.0||80||100||An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ loading samlib.dll and vaultcli.dll to potentially capture credentials in memory.|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 2