dump tool

Hunt Hypothesis

This hypothesis posits that adversaries are utilizing legitimate memory dumping utilities to extract sensitive data or credentials from running processes as part of a post-exploitation persistence strategy. The SOC team should proactively hunt for these activities in Azure Sentinel to distinguish between routine administrative tasks and potentially malicious credential harvesting, ensuring early detection before lateral movement occurs.

YARA Rule

rule dump_tool
{
meta:
	author = "@patrickrolsen"
	reference = "Related to pwdump6 and fgdump tools"
strings:
	$s1 = "lsremora"
	$s2 = "servpw"
	$s3 = "failed: %d"
	$s4 = "fgdump"
	$s5 = "fgexec"
	$s6 = "fgexecpipe"
condition:
	uint16(0) == 0x5A4D and 3 of ($s*)
}

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 6 string patterns in its detection logic.

References

• Related to pwdump6 and fgdump tools
• Source Rule

False Positive Guidance

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

• Scheduled Memory Dump by System Administrators

  • Scenario: A nightly maintenance job runs on Windows Server instances to capture memory dumps of critical services (e.g., SQL Server, Exchange) using native tools like Procdump.exe from the Microsoft Sysinternals suite or the built-in DumpIt.exe. These executions occur during off-hours via Task Scheduler under a dedicated service account.
  • Filter/Exclusion: Exclude processes where the parent process is TaskSchedulerService (or svchost.exe) and the file path matches known administrative directories, such as C:\Program Files\Microsoft Sysinternals\Procdump.exe or C:\Windows\System32\dumpit.exe.

• Automated Debugging by DevOps CI/CD Pipelines

  • Scenario: During deployment windows, the build server (e.g., Jenkins or Azure DevAgent) executes a containerized debugging utility like gdb (GNU Debugger) or windbg on temporary worker nodes to analyze application crashes. These tools are launched by the pipeline orchestrator rather than an interactive user session.
  • Filter/Exclusion: Create a rule exclusion for processes originating from known CI/CD service accounts (e.g., Jenkins-Agent, Azure-DevOps-Svc) and restrict the scope to specific build agent hostnames or IP ranges defined in the network inventory.

• Enterprise Endpoint Management Health Checks

  • Scenario: The organization’s EDR or endpoint management platform (such as CrowdStrike Falcon, Microsoft Defender for Endpoint, or Ivanti) periodically triggers a diagnostic dump tool to collect telemetry on specific agents. This often involves tools like windbg or custom wrappers invoking `CreateDump