The following analytic identifies renamed instances of msbuild.exe executing. Msbuild.exe is natively found in C:\Windows\Microsoft.NET\Framework\v4.0.30319 and C:\Windows\Microsoft.NET\Framework64\v4.0.30319. During investigation, identify the code executed and what is executing a renamed instance of MSBuild.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2021-01-12
- Author: Michael Haag, Splunk
- ID: 4006adac-5937-11eb-ae93-0242ac130002
|T1127.001||MSBuild||Defense Evasion||T1036.003||Rename System Utilities||Defense Evasion|
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_msbuild` by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.original_file_name | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `suspicious_msbuild_rename_filter`
Associated Analytic Story
- Trusted Developer Utilities Proxy Execution MSBuild
- Cobalt Strike
- Masquerading - Rename System Utilities
How To Implement
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.
Kill Chain Phase
Known False Positives
Although unlikely, some legitimate applications may use a moved copy of msbuild, triggering a false positive.
|63.0||70||90||Suspicious renamed msbuild.exe binary ran on $dest$ by $user$|
source | version: 2