Armadillov260b1

Hunt Hypothesis

This detection identifies potential malicious activity associated with the Armadillov260b1 signature, which may indicate early-stage file-based threats or specific malware variants within the environment. Proactive hunting for this indicator in Azure Sentinel is essential to uncover low-severity anomalies that could evolve into significant incidents before they trigger higher-level alerts.

YARA Rule

rule Armadillov260b1
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 55 8B EC 6A FF 68 50 [3] 68 74 [3] 64 A1 [4] 50 64 89 25 [4] 83 EC 58 53 56 57 89 65 E8 FF 15 58 [3] 33 D2 8A D4 89 15 FC }

condition:
		$a0 at pe.entry_point
}

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 1 string patterns in its detection logic.

• Source Rule

False Positive Guidance

Here are 3-5 specific false positive scenarios for the Armadillov260b1 detection rule, including suggested filters and exclusions:

• Scenario: Scheduled Endpoint Protection Scans

  • Context: The YARA signature may match the scanning engine process of enterprise EDR solutions (e.g., CrowdStrike Falcon or Microsoft Defender for Endpoint) when they perform routine heuristic scans on system directories. These tools often spawn child processes that load similar memory structures as the Armadillo malware family.
  • Filter/Exclusion: Exclude processes with executable paths containing C:\Program Files\CrowdStrike\ or C:\Windows\System32\mpcmd.exe. Additionally, filter out events where the parent process is a known service (e.g., svchost.exe) running under the SYSTEM account during off-peak hours.

• Scenario: Admin Deployment via Configuration Management Tools

  • Context: IT administrators using tools like Microsoft SCCM, Ansible, or Puppet to deploy software updates often utilize scripts that instantiate temporary agents with similar code signatures to Armadillov260b1. This is common during bulk patching windows where the deployment agent mimics the behavior of the detected malware.
  • Filter/Exclusion: Create a whitelist for processes launched by ccmexec.exe (SCCM), ansible-playbook, or puppet-agent. Filter events where the user context is a known service account (e.g., DOMAIN\DeploySvc) and the process command line contains keywords like “install,” “update,” or “deploy.”

• Scenario: Antivirus Quarantine and Remediation Jobs

  • Context: When an enterprise antivirus solution (such as Symantec Endpoint Protection or Trend Micro) isolates a file, it often creates a