BKDR_POISON.KSH

 Analysis by: Alvin Bacani

 ALIASES:

Gen:Variant.Symmi.4437 (F-Secure)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

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.

  TECHNICAL DETAILS

File Size:

61,440 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

01 Oct 2013

Payload:

Compromises system security

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.

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
FIREFOXS SERVER = "{malware path and filename}.exe"

Backdoor Routine

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

  • Send system information (Lan IP, Wan IP, Computer name, Username, Account Type, OS)
  • Send hardware information (CPU speed, Memory)
  • Manage Files (Search, Download, Upload, Execute, Rename, Delete)
  • Manage Registries (Search, Modify, Delete, Rename, Create)
  • Manage Processes (View, Kill, Suspend, Unload Module)
  • Manage Services (View, Start, Stop, Edit, Install, Uninstall)
  • Manage Devices (View, Enable, Disable, Remove)
  • Perform a shell command
  • Download and inject remote codes to legitimate processes
  • Log keystrokes and active window
  • Capture screenshots
  • Listen to microphone audio
  • Update, Uninstall, Restart the malware

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

  • USA.{BLOCKED}L.com:443

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

10.316.05

FIRST VSAPI PATTERN DATE:

03 Oct 2013

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

Scan your computer with your Trend Micro product and note files detected as BKDR_POISON.KSH

Step 3

Terminate a process file/s detected as BKDR_POISON.KSH

[ Learn More ]

*Note: If the detected file/s is/are not displayed in theWindows Task Manager, continue doing the next steps.

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • FIREFOXS SERVER = "{malware path and filename}.exe"

Step 5

Scan your computer with your Trend Micro product to delete files detected as BKDR_POISON.KSH. 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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