Backdoor.PS1.EMPOW.A

August 21, 2019
 Analysis by: Jay Garcia
 ALIASES:

PowerShell/RiskWare.Empire.A application (NOD32)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet

This Backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It does not have any propagation routine.

It executes commands from a remote malicious user, effectively compromising the affected system. However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

7,434 bytes

File Type:

PS1

Memory Resident:

Yes

Initial Samples Received Date:

13 Aug 2019

Payload:

Connects to URLs/IPs

Arrival Details

This Backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Backdoor adds the following processes:

  • net share ADMIN$ /delete
  • net share C$ /delete
  • sc.exe config wuauserv start= disabled

Propagation

This Backdoor does not have any propagation routine.

Backdoor Routine

This Backdoor executes the following commands from a remote malicious user:

  • Download a file
  • Set malware working time and date
  • Execute shell commands
  • Execute powershell commands
  • Sleep
  • Get System information
    • User domain
    • User name
    • Machine name
    • IP address
    • Operating system
  • Log Keystrokes

It connects to the following URL(s) to send and receive commands from a remote malicious user:

  • http://{BLOCKED}.{BLOCKED}.194.103:8080/admin/get.php
  • http://{BLOCKED}.{BLOCKED}.194.103:8080/news.php
  • http://{BLOCKED}.{BLOCKED}.194.103:8080/login/process.php

However, as of this writing, the said sites are inaccessible.

Rootkit Capabilities

This Backdoor does not have rootkit capabilities.

Other Details

This Backdoor does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.308.05

FIRST VSAPI PATTERN DATE:

19 Aug 2019

VSAPI OPR PATTERN File:

15.309.00

VSAPI OPR PATTERN Date:

20 Aug 2019

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Identify and terminate files detected as Backdoor.PS1.EMPOW.A

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

Scan your computer with your Trend Micro product to delete files detected as Backdoor.PS1.EMPOW.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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