The attack starts with a malicious LNK file delivered within a ZIP file, likely distributed through phishing emails, and seems to target the healthcare industry.
Upon execution, the LNK file initiates a PowerShell command that downloads multiple scripts and batch files from a remote server to establish persistence and control over the victim’s system.
The LNK file, once opened, triggers PowerShell commands that download additional payloads from hxxp://157.173.104[.]153.
These scripts enable the attacker to create a new user account with administrative privileges and alter RDP settings, reducing authentication requirements for easier unauthorized access.
A persistent shortcut (LNK) file is created in the Windows Startup folder to maintain access.
The primary PowerShell script communicates with the C2 server, constructing URLs with a unique identifier (UID) for the compromised machine to fetch commands or additional payloads.
If UAC is detected as weak or disabled, the attack proceeds with further stages that lower the system's security configurations.
A secondary payload, "ChromePass," is introduced, targeting Chromium-based browsers to harvest stored credentials, escalating the risk of compromised accounts.
Scripts configure the system to facilitate remote desktop access, enabling actions such as data exfiltration, monitoring, and installation of further malware.
Subsequent batch files (e.g., k1.bat, scheduler-once.bat) execute commands that hide traces, remove logs, and schedule tasks disguised as system operations to maintain persistence and evade detection.
The final stages involve the execution of a PowerShell script that performs reconnaissance, collects extensive system data, and sends it encoded to the C2 server.
├── 5ff89db10969cba73d1f539b12dad42c60314e580ce43d7b57b46a1f915a6a2b 202409 Resident Care Quality Improvement Strategies for Nursing Homes Enhancing Patient Satisfaction and Health Outcomes.pdf.lnk
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