Hacktool

Hunt Hypothesis

This hypothesis targets adversaries deploying specialized hacking utilities to establish persistence or conduct reconnaissance within the Azure environment. Proactive hunting is essential because these tools often mimic legitimate administrative activity, allowing attackers to operate undetected until they escalate their impact on critical assets.

YARA Rule

rule HackTool_Samples {
	meta:
		description = "Hacktool"
		score = 50
	strings:
		$a = "Unable to uninstall the fgexec service"
		$b = "Unable to set socket to sniff"
		$c = "Failed to load SAM functions"
		$d = "Dump system passwords"
		$e = "Error opening sam hive or not valid file"
		$f = "Couldn't find LSASS pid"
		$g = "samdump.dll"
		$h = "WPEPRO SEND PACKET"
		$i = "WPE-C1467211-7C89-49c5-801A-1D048E4014C4"
		$j = "Usage: unshadow PASSWORD-FILE SHADOW-FILE"
		$k = "arpspoof\\Debug"
		$l = "Success: The log has been cleared"
		$m = "clearlogs [\\\\computername"
		$n = "DumpUsers 1."
		$o = "dictionary attack with specified dictionary file"
		$p = "by Objectif Securite"
		$q = "objectif-securite"
		$r = "Cannot query LSA Secret on remote host"
		$s = "Cannot write to process memory on remote host"
		$t = "Cannot start PWDumpX service on host"
		$u = "usage: %s <system hive> <security hive>"
		$v = "username:domainname:LMhash:NThash"
		$w = "<server_name_or_ip> | -f <server_list_file> [username] [password]"
		$x = "Impersonation Tokens Available"
		$y = "failed to parse pwdump format string"
		$z = "Dumping password"
	condition:
		1 of them
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

• Microsoft Defender for Endpoint — Custom indicators / advanced hunting
• Email Gateway — Attachment scanning
• File Share Monitoring — Periodic scanning of shared drives
• YARA CLI — Manual threat hunting on endpoints

This rule contains 26 string patterns in its detection logic.

• Source Rule

False Positive Guidance

Here are 5 specific false positive scenarios for the Hacktool detection rule in an enterprise environment, along with suggested filters or exclusions:

• Scenario: Deployment of endpoint protection agents via Microsoft Endpoint Configuration Manager (SCCM/MECM) or Intune.

  • Context: When administrators push security updates or install new agent versions, the deployment engine often utilizes temporary scripts and PowerShell commands that mimic hacktool behavior to modify registry keys and inject services.
  • Filter/Exclusion: Exclude processes originating from ccmsetup.exe (SCCM) or Microsoft.IntuneManagementAgent.exe when they spawn child processes executing in the %ProgramFiles%\Microsoft Intune Management Extension\ directory.

• Scenario: Execution of scheduled network scanning and vulnerability assessment jobs.

  • Context: Automated tools like Tenable Nessus, Qualys Cloud Agent, or SolarWinds NPM run nightly scans that actively probe system configurations, install temporary drivers, and modify firewall rules to assess security posture.
  • Filter/Exclusion: Create a rule exclusion for the specific service accounts (e.g., NT SERVICE\QualysAgent or TenableNessus) running binaries such as qualyspc.exe or nessuscli.exe, provided they are launched by the Windows Task Scheduler (SchTasks.exe).

• Scenario: Administrative use of remote management and patching utilities.

  • Context: IT staff frequently utilize tools like PDQ Deploy, ManageEngine Desktop Central, or Ansible Tower to push configuration changes across thousands of endpoints. These tools often execute PowerShell scripts that modify system settings and install temporary diagnostic utilities.
  • Filter/Exclusion: Whitelist the executable paths for known management suites (e.g., C:\Program Files\PDQ Deploy\pdqdeploy.exe or `C:\Program Files\ManageEngine\Desktop Central