Modified by: Jed Valderama
ALIASES:

Backdoor:Win32/Simbot.gen (Microsoft); Downloader (Symantec); Trojan-Downloader.Win32.Rubinurd.f, Trojan-Downloader.Win32.Rubinurd.f (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); ERROR (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Dropped by other malware

This backdoor may be dropped by other malware.

However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size: 11,776 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 18 Apr 2012
Payload: Connects to URLs/IPs, Compromises system security

Arrival Details

This backdoor may be dropped by other malware.

Installation

This backdoor is injected into the following processes running in memory:

  • notepad.exe
  • svchost.exe
  • services.exe

Backdoor Routine

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

  • http://{BLOCKED}2.{BLOCKED}6.55.210:443/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}.0.{BLOCKED}8.242:443/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}2.{BLOCKED}.148.242:80/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}.{BLOCKED}.78.174:443/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}6.{BLOCKED}6.0.37:443/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}2.{BLOCKED}6.55.210/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}2.0.{BLOCKED}8.242/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}4.{BLOCKED}2.78.174/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}6.{BLOCKED}6.0.37/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}9.{BLOCKED}5.141.102:443/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}9.{BLOCKED}5.141.102/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}8.{BLOCKED}3.69.189:80/{five random letters}.php?id={random numbers}
  • http://{BLOCKED}3.{BLOCKED}6.72.232:2600/user.jsp?{random 2 chars}={random}{username hash}

However, as of this writing, the said sites are inaccessible.

Other Details

Based on analysis of the codes, it has the following capabilities:

  • Send target machine's MAC address
  • Remotely execute arbitrary commands.
  • Download and remotely execute other malware

NOTES:

Upon installation, this backdoor is injected to the said processes by these malware:

  SOLUTION

Minimum Scan Engine: 9.700
FIRST VSAPI PATTERN FILE: 8.921.00
FIRST VSAPI PATTERN DATE: 18 Apr 2012

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_SIMBOT.SMC

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Search and delete the files detected as BKDR_SIMBOT.SMC

*Note: Some component files may be 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.

To stop the malware/grayware from running when certain files are opened:

For Windows 2000, Windows XP, and Windows Server 2003:

  1. Right-click Start then click Search....
  2. In the File name* input box, type the name of the file that was detected earlier.
  3. In the Look In drop-down list, select My Computer then press Enter.
  4. Once located, select the file then press SHIFT+DELETE to delete it.
    *Note: The file name input box title varies depending on the Windows version (e.g. Search for files or folders named or All or part of the file name.).

For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012 (R2):

  1. Open a Windows Explorer window.
    • For Windows Vista, 7, and Server 2008 users, click Start>Computer.
    • For Windows 8, 8.1, and Server 2012 users, right-click on the lower left corner of the screen,then click File Explorer.
  2. In the Search Computer/This PC input box, type the name of the file that was detected earlier.
  3. Once located, select the file then press SHIFT+DELETE to delete it.
    *Note: Read the following Microsoft page if these steps do not work on Windows 7.

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_SIMBOT.SMC. 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.

NOTES:

Remove malware/grayware files that injected BKDR_SIMBOT.SMC:


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