Analysis by: John Kevin Sanchez
ALIASES:

Trojan:Win32/Skeeyah.A!rfn (Microsoft), Infostealer.Limitail (Symantec), hacktool.msil.boilod.a (Invincea)

 PLATFORM:

Windows

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

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This spyware may be downloaded by other malware/grayware from remote sites.

  TECHNICAL DETAILS

File Size: 155,648 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 24 Nov 2016
Payload: Connects to URLs/IPs, Steals information

Arrival Details

This spyware may be downloaded by the following malware/grayware from remote sites:

  • W2KM_DONOFF.YBC

Installation

This spyware drops the following copies of itself into the affected system:

  • %Application Data%\Java\JavaUpdtr.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:

  • %Application Data%\Java

(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 spyware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Windows
Load = %Application Data%\Java\JavaUpdtr.exe

Backdoor Routine

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

  • www.{BLOCKED}esla.com
    Type of data sent:
    • type={0}&hwid={1}&time={2}&pcname={3}&logdata={4}&screen={5}&ipadd={6}&webcam_link={7}&client={8}&link={9}&username={10}&password={11}&screen_link={12}&site_username={13}

      where:
      0 is a command which can be:
      webcam - send images caught by webcam to C&C
      screenshots - send screenshots to C&C
      keylog - send keystroke logs to C&C
      update - update the keylogger software
      info - send machine information to C&C
      uninstall - uninstall binary
      passwords - send stolen password to C&C

    Information Theft

    This spyware gathers the following data:

    • Screenshots
    • Webcam capture
    • Keystrokes including clipboards
    • Steals password from:
      • Chrome
      • Opera
      • Yandex
      • Firefox
      • Internet Explorer
      • Safari
      • SeaMonkey
      • Comodo
      • Coolnovo
      • Chromium
      • Flock
      • Outlook
      • Thunderbird
      • TheBat!
      • PocoMail
      • Eudora
      • FoxMail
      • Opera Mail
      • FileZilla
      • WinSCP
      • FlashFXP
      • CoreFTP
      • FTPCommander
      • SmartFTP
      • WS_FTP
      • Paltalk
      • Internet Download Manager
      • JDownloader
      • Pidgin
      • NO-IP
      • DynDNS

    Other Details

    This spyware connects to the following URL(s) to get the affected system's IP address:

    • http://checkip.{BLOCKED}s.org/

    It does the following:

    • Terminate a process
    • Disable task manager, regedit, command prompt, run, control panel, system restore, folder options, MS config
    • Display fake error message

    • Uninstall self from victim’s machine

    NOTES:

  SOLUTION

Minimum Scan Engine: 9.800

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 NT\CurrentVersion\Windows
    • Load = %Application Data%\Java\JavaUpdtr.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.
  • %Application Data%\Java

Step 6

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


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