arrow_back
search
close

BKDR_NOSRAWEC.AD

November 22, 2013
 Analysis by: Anthony Joe Melgarejo
 ALIASES:

Backdoor:Win32/Nosrawec.A (Microsoft), a variant of Win32/SchwarzeSonne.B trojan (ESET)

 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:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW


This Trojan may be downloaded from remote sites by other malware.

It executes commands from a remote malicious user, effectively compromising the affected system.

  TECHNICAL DETAILS

File Size:

585,728 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

14 Jun 2013

Arrival Details

This Trojan may be downloaded from remote site(s) by the following malware:

Installation

This Trojan drops the following copies of itself into the affected system and executes them:

  • %User Temp%\test.exe

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

It terminates the execution of the copy it initially executed and executes the copy it drops instead.

Backdoor Routine

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

  • Manage files, processes, services and windows
  • Perform screen, webcam, audio, keylog and passwords surveillance.
  • Edit the registry.
  • Perform remote shell.
  • Edit and run scripts.

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

  • {BLOCKED}.{BLOCKED}.252.125:5555

NOTES:

The URL it accesses is a private IP address. Therefore, its C&C server is a host in the Local Area Network (LAN).

This file may have been created for testing purposes or the said IP address in its LAN may have been compromised. This is the server component of HKTL_PANRAT.

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

9.982.02

FIRST VSAPI PATTERN DATE:

14 Jun 2013

VSAPI OPR PATTERN File:

9.983.00

VSAPI OPR PATTERN Date:

14 Jun 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

Remove the malware/grayware file that dropped/downloaded BKDR_NOSRAWEC.AD

    • TROJ_NOSRAWEC.AD

Step 3

Terminate a malware/grayware process

[ Learn More ]

*Note: If the detected process is not displayed in theWindows Task Manager, continue doing the next steps.

    • test.exe

Step 4

Scan your computer with your Trend Micro product to delete files detected as BKDR_NOSRAWEC.AD. 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.


Did this description help? Tell us how we did.