TrojanSpy.Win32.FAUXPERSKY.AA

 Analysis by: Ricardo III Valdez
 Modified by: Jeffrey Francis Bonaobra

 PLATFORM:

Windows

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

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

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

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size:

881,152 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

08 Feb 2023

Payload:

Connects to URLs/IPs, Collects system information, Steals information, Deletes files

Arrival Details

This Trojan Spy 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 Trojan Spy adds the following processes:

  • %System%\cmd.exe /c ping -n 1 -w 1000 www.google.com.my>Ping.sb → checks internet connection
  • {Malware file path}\winlogin.exe → if not running in the system
  • %AppData%\Temp.exe → if file is downloaded successfully

Other System Modifications

This Trojan Spy deletes the following files:

  • {Malware file path}\S_Core.txt
  • {Malware file path}\S_CMD.txt
  • {Malware file path}\S_PTC.txt

Process Termination

This Trojan Spy terminates the following processes if found running in the affected system's memory:

  • msiexec.exe

Download Routine

This Trojan Spy accesses the following websites to download files:

  • https://kasperskypure.{BLOCKED}pp.com/S_Core.txt
  • https://kasperskypure.{BLOCKED}pp.com/S_CMD.txt
  • https://kasperskypure.{BLOCKED}pp.com/S_PTC.txt
  • https://kasperskypure.{BLOCKED}pp.com/spoolsvc.exe → downloaded to update existing files in the system
  • https://kasperskypure.{BLOCKED}pp.com/Temp.exe → downloaded to update existing files in the system

It saves the files it downloads using the following names:

  • {Malware file path}\S_Core.txt
  • {Malware file path}\S_CMD.txt
  • {Malware file path}\S_PTC.txt
  • {Malware file path}\spoolsvc.exe
  • %AppData%\Temp.exe

Information Theft

This Trojan Spy gathers the following data:

  • OS Version
  • Computer Name
  • User Name
  • IP Address
  • Content:
    • Update number of downloaded files, spoolsvc.exe and Temp.exe
    • Success message if execution of downloaded files are successful

Other Details

This Trojan Spy connects to the following URL(s) to check for an Internet connection:

  • www.google.com.my

It connects to the following website to send and receive information:

  • https://docs.google.com/forms/d/e/{BLOCKED}LSe6oGStKSshScVonAyCVFOrhANSfnmm0Im-aabnBX5ZjLabbA/viewform?entry.{BLOCKED}914=%A_OSVersion%&entry.{BLOCKED}477=%A_ComputerName%&entry.{BLOCKED}695=%A_UserName%&entry.{BLOCKED}0660=%A_IPAddress1%

It does the following:

  • It checks the contents of Ping.sb if it contains the string "could not find".
    • If found, it repeatedly checks for internet connection.
  • It checks if all the components of the malware are already running.
  • It checks if the following files are present in the directory where the sample is located:
    • winlogin.exe → executed if found
    • spoolsvc.exe
      • If found:
        • It compares the last update time of spoolsvc.exe with S_Core.txt.
        • If outdated, it downloads the updated version of the file.
  • It checks if the following files are present in %AppData%:
    • Temp.exe
      • It downloads the file if not found.
      • It compares the last update time of Temp.exe with S_CMD.txt.
      • If outdated, it downloads the updated version of the file.
  • It sets the file attributes of the following files to Read-Only, Hidden, and System:
    • {Malware file path}\spoolsvc.exe
    • %AppData%\Temp.exe
  • It exfiltrates information via Google Forms.

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

18.254.03

FIRST VSAPI PATTERN DATE:

13 Feb 2023

VSAPI OPR PATTERN File:

18.255.00

VSAPI OPR PATTERN Date:

14 Feb 2023

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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Identify and terminate files detected as TrojanSpy.Win32.FAUXPERSKY.AA

[ 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 4

Search and delete these files

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.  
  • {Malware file path}\Ping.sb
  • {Malware file path}\S_Core.txt
  • {Malware file path}\S_CMD.txt
  • {Malware file path}\S_PTC.txt
  • {Malware file path}\spoolsvc.exe
  • %AppData%\Temp.exe

Step 5

Scan your computer with your Trend Micro product to delete files detected as TrojanSpy.Win32.FAUXPERSKY.AA. 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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