Analysis by: Noel Anthony Llimos


Trojan:Win32/Tiggre!plock (Microsoft) Win32:DangerousSig [Trj] (Avast)




  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes


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.


File Size: 381,928 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 28 Aug 2018
Payload: Steals information, 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.

This malware arrives via the following means:

Backdoor Routine

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

  • Alternate Parent Process
  • Change file time
  • Escalate privilege
  • Execute PowerShell commands
  • File System Commands
  • Get Drives
  • Inject Code into a process
  • List Processes
  • Manage Service
  • Open a process
  • Sleep
  • Steal or Make token
  • Terminate process
  • Upload and Download Files
  • Use and Purge Kerberos Tickets
  • Create, Connect and Disconnect to named pipe
  • Add or modify an environment variable

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

  • http://{Random}.img.{BLOCKED}

Information Theft

This Backdoor gathers the following data:

  • Malware Process ID
  • Operating System
  • CPU ID
  • Operating System Version
  • IP Address
  • Computer Name
  • User name

Stolen Information

This Backdoor sends the gathered information via HTTP POST to the following URL:

  • http://{Random}.content.{BLOCKED}{Random}

Other Details

This Backdoor does the following:

  • It uses a named pipe to send and receive commands.


Minimum Scan Engine: 9.850
VSAPI OPR PATTERN File: 14.473.00
VSAPI OPR PATTERN Date: 30 Aug 2018

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

Identify and terminate files detected as BKDR_COBEACON.QNA

[ 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

Scan your computer with your Trend Micro product to delete files detected as BKDR_COBEACON.QNA. 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:

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