This detection identifies the presence of report.dll, a known component of the Chinese Hacktool set often associated with supply chain compromises or initial reconnaissance activities by state-sponsored actors. Proactively hunting for this artifact in Azure Sentinel is critical to validate its legitimacy against baseline configurations and uncover potential lateral movement vectors before they escalate into significant data exfiltration events.
rule dat_report {
meta:
description = "Chinese Hacktool Set - file report.dll"
author = "Florian Roth"
reference = "http://tools.zjqhr.com/"
date = "2015-06-13"
hash = "4582a7c1d499bb96dad8e9b227e9d5de9becdfc2"
strings:
$s1 = "<a href=\"http://www.xfocus.net\">X-Scan</a>" fullword ascii
$s2 = "REPORT-ANALYSIS-OF-HOST" fullword ascii
condition:
uint16(0) == 0x5a4d and filesize < 480KB and all of them
}
This YARA rule can be deployed in the following contexts:
This rule contains 2 string patterns in its detection logic.
Here are 4 specific false positive scenarios for the Chinese Hacktool Set - file report.dll detection rule, along with suggested filters or exclusions:
Scenario: Automated Reporting via Microsoft Power BI Desktop
report.dll component within the %LOCALAPPDATA%\Microsoft\PowerBI Desktop\cache directory during refresh cycles or when exporting paginated reports. This legitimate file creation often mimics the behavior of Chinese hacktools that inject DLLs for monitoring.\Microsoft\PowerBI Desktop\ and specifically filter for report.dll where the parent process is MSBuild.exe or PowerBIDesktop.exe.Scenario: Scheduled System Health Checks by SolarWinds Service Desk
report.dll in the installation directory (C:\Program Files\SolarWinds\...) to compile system performance metrics before uploading them to the central server.C:\Program Files\SolarWinds\ where the process name is SMSEngine.exe or SolarWindsAgent.exe, and the file creation time aligns with the scheduled maintenance window (e.g., 02:00–04:00 UTC).Scenario: Deployment of Oracle APEX Reports Module
report.dll file to support dynamic report rendering