Windows BootLoader Inventory
Description
The following analytic identifies the bootloader paths on Windows endpoints. It leverages a PowerShell Scripted input to capture this data, which is then processed and aggregated using Splunk. Monitoring bootloader paths is significant for a SOC as it helps detect unauthorized modifications that could indicate bootkits or other persistent threats. If confirmed malicious, such activity could allow attackers to maintain persistence, bypass security controls, and potentially control the boot process, leading to full system compromise.
Query · spl
`bootloader_inventory`
| stats count min(_time) as firstTime max(_time) as lastTime values(_raw)
BY host
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_bootloader_inventory_filter`
Implementation guide
To implement this analytic, a new stanza will need to be added to a inputs.conf and deployed to all or some Windows endpoints. https://gist.github.com/MHaggis/26518cd2844b0e03de6126660bb45707 provides the stanza. If modifying the sourcetype, be sure to update the Macro for this analytic. Recommend running it daily, or weekly, depending on threat model.
Known false positives
- No false positives here, only bootloaders. Filter as needed or create a lookup as a baseline.
Analyst notes
Known false positives: No false positives here, only bootloaders. Filter as needed or create a lookup as a baseline.