Analysis by: Michael John Marcos
ALIASES:

Win32/Jinupd.B (Microsoft)

 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: Dropped by other malware, 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 runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the computer at greater risk.

It deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size: 242688 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 22 Mar 2014
Payload: Compromises system security, 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 drops the following files:

  • %User Temp%\svchost.exe (watchdog component)

(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 drops the following copies of itself into the affected system:

  • %Application Data%\Java SE Platform Updater\{file name}.exe

(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.)

It creates the following folders with attributes set to System and Hidden to prevent users from discovering and removing its components:

  • %Application Data%\Java SE Platform Updater

(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.)

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Java SE Platform Updater = "%Application Data%\Java SE Platform Updater\{file name}.exe"

Other System Modifications

This backdoor adds the following registry entries:

HKEY_CURRENT_USER\Software\Javaw
Pid = {Process ID of executed dropped copy of itself}

HKEY_CURRENT_USER\Software\Javaw
Pid1 = {Process ID of executed watchdog program}

Backdoor Routine

This backdoor executes the following command(s) from a remote malicious user:

  • kill - Remove itself from the system
  • update - Updates itself
  • exec - Execute program

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

  • http://{BLOCKED}s.hk

It posts the following information to its command and control (C&C) server:

  • mac = Computer MAC Address
  • t1 = credit card's data track 1
  • t2 = credit card's data track 2

Other Details

This backdoor deletes the initially executed copy of itself

NOTES:

Where {file name} can be any of the following:

  • jusched
  • jucheck
  • javaw
  • jureg
  • jse
  • java
  • javaws
  • javacpl

This backdoor launches a watchdog process (%User Temp%\svchost.exe) to ensure that it continuously runs in the system.

It uses data in HKEY_CURRENT_USER\Software\Javaw\Pid and HKEY_CURRENT_USER\Software\Javaw\Pid1 to check if the process is running. This watchdog process only works on Windows Vista and above.

It scans the memory of all running processes to retrieve credit card's data track 1 and 2.

It skips to scan 64-bit processes.

It skips to scan the following processes:

  • System
  • [System Process]
  • smss.exe
  • csrss.exe
  • winlogon.exe
  • services.exe
  • lsass.exe
  • svchost.exe
  • spoolsv.exe
  • wscntfy.exe
  • alg.exe
  • mscorsvw.exe
  • ctfmon.exe
  • System Process
  • taskhost.exe
  • dwm.exe
  • skype.exe

The following is the template of the data it sends using HTTP POST:

mac={Computer's MAC Address}t1={Credit card data track 1}t2={Credit card data track 2}

  SOLUTION

Minimum Scan Engine: 9.700

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

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this 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
    • Java SE Platform Updater = "%Application Data%\Java SE Platform Updater\{file name}.exe"
  • In HKEY_CURRENT_USER\Software\Javaw
    • Pid = {Process ID of executed dropped copy of itself}
  • In HKEY_CURRENT_USER\Software\Javaw
    • Pid1 = {Process ID of executed watchdog program}

Step 4

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.
  • %Application Data%\Java SE Platform Updater\{file name}.exe

Step 5

Search and delete this folder

[ 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.
  • %Application Data%\Java SE Platform Updater

Step 6

Scan your computer with your Trend Micro product to delete files detected as BKDR_JACKPOS.C. 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.

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_JACKPOS.C. 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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