Windows Executable in Loaded Modules
Description
The following analytic identifies instances where executable files (.exe) are loaded as modules, detected through 'ImageLoaded' events in Sysmon logs. This method leverages Sysmon EventCode 7 to track unusual module loading behavior, which is significant as it deviates from the norm of loading .dll files. This activity is crucial for SOC monitoring because it can indicate the presence of malware like NjRAT, which uses this technique to load malicious modules. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, maintain persistence, and further compromise the host system.
Query · spl
`sysmon` EventCode=7 ImageLoaded != *.dll AND Signed != true
| fillnull
| 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
Signed signature_id user_id
vendor_product
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_executable_in_loaded_modules_filter`
Implementation guide
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
- No false positives have been identified at this time.
Analyst notes
Known false positives: No false positives have been identified at this time.