TrojanSpy.Win32.ROKRAT.AB

May 17, 2019
 Analysis by: Earle Maui Earnshaw
 PLATFORM:

Windows

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

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted:

  • 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.

  TECHNICAL DETAILS

File Size:

1,643,520 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

15 May 2019

Payload:

Steals information, Connects to URLs/IPs, Drops files, Logs keystrokes

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 creates the following folders:

  • %Application Data%\{11 random characters}
  • %Application Data%\{11 random characters}\{8 - 12 random characters} → Will create 8 different folders in the created {11 random characters} directory
  • %Application Data%\Adobe Update

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

Dropping Routine

This Trojan Spy drops the following files:

  • %Application Data%\{11 random characters}\{8 - 12 random characters}\10{5 random characters}.pdb
  • %Application Data%\Adobe Update\JSNS.dat
  • %Application Data%\{11 random characters}\{8 - 12 random characters}\doumo.cfdb
  • %Application Data%\{11 random characters}\{8 - 12 random characters}\doumo.cfdb-journal
  • %Application Data%\{11 random characters}\{8 - 12 random characters}\{found file satisfying the conditions below}.enc → Contains the path of the file and appends garbage code that serves as a fake network traffic log
  • %Application Data%\ccc.conf

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

Information Theft

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

  • Firefox
  • Internet Explorer
  • Google Chrome

Other Details

This Trojan Spy does the following:

  • Attempts communication to the following URLs to send, receive commands and download additional files:
    • https://{BLOCKED}i.{BLOCKED}x.com/oauth2/token
    • https://{BLOCKED}t.{BLOCKED}x.com/api/oauth2/authorize
    • https://{BLOCKED}i.{BLOCKED}x.com/2.0/folders/%s/items
    • https://{BLOCKED}i.{BLOCKED}x.com/2.0/folders
    • https://{BLOCKED}i.{BLOCKED}x.com/2.0/files/%s/content
    • https://{BLOCKED}i.{BLOCKED}x.com/2.0/files/%s
    • https://{BLOCKED}i.{BLOCKED}x.com/2.0/files/%s/trash
    • https://{BLOCKED}d.{BLOCKED}x.com/api/2.0/files/content
    • https://{BLOCKED}i.{BLOCKED}xapi.com/2/files/list_folder
    • https://{BLOCKED}i.{BLOCKED}xapi.com/2/files/create_folder
    • https://{BLOCKED}i.{BLOCKED}xapi.com/2/files/delete
    • https://{BLOCKED}t.{BLOCKED}xapi.com/2/files/upload
    • https://{BLOCKED}t.{BLOCKED}xapi.com/2/files/download
    • https://{BLOCKED}i.{BLOCKED}d.com/oauth2_token
    • https://{BLOCKED}y.{BLOCKED}d.com/oauth2/authorize
    • https://{BLOCKED}i.{BLOCKED}d.com/listfolder?path=%s
    • https://{BLOCKED}i.{BLOCKED}d.com/createfolder?path=%s
    • https://{BLOCKED}i.{BLOCKED}d.com/uploadfile?path=%s&filename=%s&nopartial=1
    • https://{BLOCKED}i.{BLOCKED}d.com/getfilelink?path=%s&forcedownload=1&skipfilename=1
    • https://{BLOCKED}i.{BLOCKED}d.com/deletefile?path=%s
    • https://{BLOCKED}api.{BLOCKED}x.net/v1/disk/resources?path=%s&limit=500
    • https://{BLOCKED}api.{BLOCKED}x.net/v1/disk/resources/?path=%s
    • https://{BLOCKED}api.{BLOCKED}x.net/v1/disk/resources?path=%s&permanently=%s
    • https://{BLOCKED}api.{BLOCKED}x.net/v1/disk/resources/upload?path=%s&overwrite=%s
    • https://{BLOCKED}api.{BLOCKED}x.net/v1/disk/resources/download?path=%s

    When sending the stolen information it uses the following predefined directory path in place of the %s:
    • english
    • video
    • scriptout
  • It is capable of the following:
    • Saving screenshots of the infected computer
    • Audio recording
    • Directory listing
    • Disk info gathering
    • Logging keystrokes
    • Updating configuration data including cloud service token information
  • Search for the following file extensions to create a fake network traffic log:
    • .rwp
    • .doc
    • .docx
    • .pdf
    • .rtf
    • .xls
    • .xlsx
    • .txt
    • .msg
    • .ppt
    • .pptx
    • .eml
    • .pps
    • .hwp → Hangul Word Processor
  • It avoids the following directories in finding files to create a fake network traffic log:
    • appdata
    • HNC
    • windows
    • Program Files
    • Program Files (x86)

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.116.04

FIRST VSAPI PATTERN DATE:

17 May 2019

VSAPI OPR PATTERN File:

15.117.00

VSAPI OPR PATTERN Date:

18 May 2019

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.ROKRAT.AB

[ 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 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%\Adobe Update
  • %Application Data%\{11 random characters}

Step 5

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%\ccc.conf

Step 6

Scan your computer with your Trend Micro product to delete files detected as TrojanSpy.Win32.ROKRAT.AB. 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:


Did this description help? Tell us how we did.