Emerging Threatmediumtest

ScreenConnect User Database Modification

Detects file modifications to the temporary xml user database file indicating local user modification in the ScreenConnect server. This will occur during exploitation of the ScreenConnect Authentication Bypass vulnerability (CVE-2024-1709) in versions <23.9.8, but may also be observed when making legitimate modifications to local users or permissions.

Convert In Phoenix Studio

Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.

Launch
Matt Anderson, Andrew Schwartz, Caleb Stewart, HuntressCreated Wed Feb 211a821580-588b-4323-9422-660f7e1310202024
Emerging Threat
Active Threat

Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.

Log Source
WindowsFile Event
ProductWindows← raw: windows
CategoryFile Event← raw: file_event

Events for file system activity including creation, modification, and deletion.

Detection Logic
Detection Logic1 selector
detection:
    selection:
        TargetFilename|endswith: '.xml'
        TargetFilename|contains|all:
            - 'Temp'
            - 'ScreenConnect'
        Image|endswith: '\ScreenConnect.Service.exe'
    condition: selection
False Positives

This will occur legitimately as well and will result in some benign activity.