LoFP LoFP / false positives will only be present if a process legitimately writes a .cab file to disk. modify the analytic as needed by file path. filter as needed.

Techniques

Sample rules

Windows CAB File on Disk

Description

The following analytic detects .cab files being written to disk. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on events where the file name is ‘*.cab’ and the action is ‘write’. This activity is significant as .cab files can be used to deliver malicious payloads, including embedded .url files that execute harmful code. If confirmed malicious, this behavior could lead to unauthorized code execution and potential system compromise. Analysts should review the file path and associated artifacts for further investigation.

Detection logic


| tstats `security_content_summariesonly` count values(Filesystem.file_path) as file_path min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Filesystem where (Filesystem.file_name=*.cab) by Filesystem.action Filesystem.dest Filesystem.file_access_time Filesystem.file_create_time Filesystem.file_hash Filesystem.file_modify_time Filesystem.file_name Filesystem.file_path Filesystem.file_acl Filesystem.file_size Filesystem.process_guid Filesystem.process_id Filesystem.user Filesystem.vendor_product 
| `drop_dm_object_name("Filesystem")` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_cab_file_on_disk_filter`