Analysis by: Rika Joi Gregorio
ALIASES:

a variant of MSIL/Kryptik.AAK trojan(Eset), MSIL/Kryptik.AAK!tr(Fortinet)

 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

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.

  TECHNICAL DETAILS

File Size: 648,192 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 29 Dec 2014
Payload: Connects to URLs/IPs, Steals information

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:

  • %Application Data%\Imminent\Logs\{date of first execution}
  • %Application Data%\Imminent\Logs\Path.dat

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

  • %System Root%\system32\update.exe
  • %Application Data%\system32\update.exe

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %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:

  • %System Root%\system32
  • %Application Data%\Imminent
  • %Application Data%\Imminent\Logs
  • %Application Data%\system32

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %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
windows = "%Application Data%\system32\update.exe"

Backdoor Routine

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

  • Download file/data
  • Open and close CD-ROM drive door
  • Shutdown
  • Load/Unload plugins
  • Download/Start/Stop miner
  • Spread using torrent (uTorrent, BitTorrent, Azureus)
  • Disable task manager
  • Run as a proxy
  • Terminate process
  • Start keylogging
  • Injects to process
  • Delete file
  • Uninstall itself
  • List webcams and monitor/capture video
  • Get/Set clipboard data
  • Update itself
  • Upload files
  • Start and control chat sessions
  • Capture screenshots
  • Perform remote shell

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

  • crackbabynetworks.{BLOCKED}p.biz

Information Theft

This backdoor gathers the following data:

  • AV product installed
  • Firewall product installed
  • System information (Processor, graphic card)

It attempts to get stored information such as user names, passwords, and hostnames from the following browsers:

  • Google Chrome
  • Mozilla Firefox

  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

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

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
    • windows = "%Application Data%\system32\update.exe"

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.
  • %System Root%\system32
  • %Application Data%\Imminent
  • %Application Data%\system32

Step 6

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