JAVA_ADWIND.AUJC

 Analysis by: Joselyn Canuela

 ALIASES:

JV/Backdoor-Adwind.b (McAfee), Trojan.Java.Crypt (Ikarus), HEUR:Trojan.Java.Agent.gen (Kaspersky)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


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 executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.

It gathers information and reports it to its servers.

  TECHNICAL DETAILS

File Size:

814,142 bytes

File Type:

JAR

Memory Resident:

Yes

Initial Samples Received Date:

09 May 2017

Payload:

Connects to URLs/IPs, Compromises system security

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 drops the following copies of itself into the affected system and executes them:

  • %User Profile%\SSyjJfwfiRB\JFCQAmPESvV.FAdufi

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

It drops the following files:

  • %System%\test.txt -> used to check for admin rights
  • %User Profile%\{SSyjJfwfiRB}\ID.txt -> contains UUID
  • %User Temp%\Retrive{random numbers}.vbs -> script to detect installed AV security and Firewall products (deleted after execution)
  • %User Profile%\fUTkALeaTxM\ID.txt -> contains UUID
  • %User Temp%\hsperfdata_{username}\{random} -> contains details of the malware
  • %ProgramData%\Java\.oracle_jre_usage\{random}.timestamp -> time usage of oracle

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData in Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It drops and executes the following files:

  • %User Temp%\0.{random numbers}.class -> class to be loaded by main executable JAR, also detected as JAVA_ADWIND.AUJC

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It adds the following processes:

  • attrib +h "%User Profile%\{random characters}\*.*" -> set attribute of all files under the folder to hidden
  • attrib +h "%User Profile%\{random characters}" -> set attribute of folder to hidden
  • xcopy "%Program Files%\Java\jre{version}" "%Application Data%\Oracle\" /e -> copy files and directory trees of Java Installation folder to %Application Data%\Oracle folder

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It creates the following folders:

  • %Application Data%\Oracle
  • %User Profile%\fUTkALeaTxM
  • %User Profile%\SSyjJfwfiRB\ELuWKLWnsRe -> plugin folder
  • %User Profile%\SSyjJfwfiRB
  • %User Temp%\hsperfdata_{User Name}
  • %ProgramData%\Java\.oracle_jre_usage

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData in Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Autostart Technique

This Backdoor modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
fgovbdbXqNj = %Application Data%\Oracle\bin\javaw.exe" -jar "%User Profile%\SSyjJfwfiRB\JFCQAmPESvV.FAdufi"

Backdoor Routine

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

  • Download Plug-ins
  • Download and Execute Files
  • Update itself
  • Uninstall itself
  • Reset Connection
  • Terminate Process
  • Sceen Capture
  • Access Webcam
  • Log Keystrokes

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

  • {BLOCKED}bk.{BLOCKED}s.net:6050

Other Details

This Backdoor gathers the following information and reports it to its servers:

  • Local IP
  • Mac Address
  • Size of RAM
  • Country
  • User Name
  • OS Name
  • OS Version
  • If User is Admin
  • Java Version

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.398.04

FIRST VSAPI PATTERN DATE:

11 May 2017

VSAPI OPR PATTERN File:

13.395.00

VSAPI OPR PATTERN Date:

12 May 2017

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 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

Restart in Safe Mode

[ Learn More ]

Step 4

Restore this modified registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • fgovbdbXqNj = ""%Application Data%\Oracle\bin\javaw.exe" -jar "%User Profile%\SSyjJfwfiRB\JFCQAmPESvV.FAdufi""

Step 5

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\fUTkALeaTxM
  • %User Profile%\SSyjJfwfiRB
  • %User Temp%\hsperfdata_{User Name}
  • %ProgramData%\Java\.oracle_jre_usage
  • %Application Data%\Oracle

Step 6

Search and delete this file

[ 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.
  • %User Temp%\0.{random numbers}.class
  • %System%\test.txt

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as JAVA_ADWIND.AUJC. 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 this Knowledge Base page for more information.


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