Detection: Windows Bitsadmin Download File
Description
The following query identifies Microsoft Background Intelligent Transfer Service utility bitsadmin.exe using the transfer parameter to download a remote object. In addition, look for download or upload on the command-line, the switches are not required to perform a transfer. Capture any files downloaded. Review the reputation of the IP or domain used. Typically once executed, a follow on command will be used to execute the dropped file. Note that the network connection or file modification events related will not spawn or create from bitsadmin.exe, but the artifacts will appear in a parallel process of svchost.exe with a command-line similar to svchost.exe -k netsvcs -s BITS. It's important to review all parallel and child processes to capture any behaviors and artifacts. In some suspicious and malicious instances, BITS jobs will be created. You can use bitsadmin /list /verbose to list out the jobs during investigation.
Annotations
No annotations available.
Implementation
To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the Endpoint datamodel in the Processes node. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.
Known False Positives
Limited false positives, however it may be required to filter based on parent process name or network connection.
Associated Analytic Story
Risk Based Analytics (RBA)
| Risk Message | Risk Score | Impact | Confidence |
|---|---|---|---|
| An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $dest_user_id$ attempting to download a file. | 49 | 70 | 70 |
References
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https://docs.microsoft.com/en-us/windows/win32/bits/bitsadmin-tool
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https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
Version: 4