Detection: Windows DLL Module Loaded in Temp Dir

Updated Date: 2025-08-20 ID: c2998141-235a-4e31-83cf-46afb5208a87 Author: Teoderick Contreras, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic detects instances where a Dynamic Link Library (DLL) is loaded from a temporary directory on a Windows system. Loading DLLs from non-standard paths such as %TEMP% is uncommon for legitimate applications and is often associated with adversary tradecraft, including DLL search order hijacking, side-loading, or execution of malicious payloads staged in temporary folders. Adversaries frequently leverage these directories because they are writable by standard users and often overlooked by security controls, making them convenient locations to drop and execute malicious files. This behavior may indicate attempts to evade detection, execute unauthorized code, or maintain persistence through hijacked execution flows. Detection of DLL loads from %TEMP% can help surface early signs of compromise and should be investigated in the context of the originating process, user account, and potential file creation or modification activity within the same directory.

Search

1`sysmon` EventCode=7 NOT (ImageLoaded IN("C:\\Program Files*")) AND ImageLoaded="*\\temp\\*" AND ImageLoaded="*.dll" 
2| fillnull 
3| stats count min(_time) as firstTime max(_time) as lastTime by Image ImageLoaded dest loaded_file loaded_file_path original_file_name process_exec process_guid process_hash process_id process_name process_path service_dll_signature_exists service_dll_signature_verified signature signature_id user_id vendor_product 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_dll_module_loaded_in_temp_dir_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 7	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_dll_module_loaded_in_temp_dir_filter	`search *`

windows_dll_module_loaded_in_temp_dir_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
T1105	Ingress Tool Transfer	Command And Control

Command and Control

DE.AE

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 Risk Event	False

This configuration file applies to all detections of type hunting.

Implementation

To successfully implement this search, you need to be ingesting logs with the process name and imageloaded executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

unknown

Associated Analytic Story

Interlock Rat

References

Detection Testing

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