TROJ_SEFNIT.CY

October 09, 2012
 Analysis by: Erika Bianca Mendoza
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

  TECHNICAL DETAILS

File Size:

128,969 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

12 Jan 2012

Payload:

Connects to URLs/IPs

Arrival Details

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This Trojan drops and executes the following files:

  • %Application Data%\odbcHelpNetM\MSNComms32.dll - also detected as TROJ_SEFNIT.CY

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

It creates the following folders:

  • %Application Data%\odbcHelpNetM

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

It injects threads into the following normal process(es):

  • firefox.exe

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
MSNComms32 = rundll32.exe %Application Data%\odbcHelpNetM\MSNComms32.dll,CRLnetInterval rasnetppm

NOTES:

This Trojan comes with an installer that executes its DLL component. The DLL component is injected to a browser process to monitor search requests from the following search engines:

  • Bing
  • Google
  • Yahoo

It also affects Mozilla Firefox web browser.

The search queries redirect to the following website:

  • http://{BLOCKED}.{BLOCKED}.161.29:8180/feed/go.php

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

8.704.10

FIRST VSAPI PATTERN DATE:

12 Jan 2012

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • MSNComms32 = rundll32.exe %Application Data%\odbcHelpNetM\MSNComms32.dll,CRLnetInterval rasnetppm

Step 4

Search and delete this file

[ Learn More ]
There may be some component 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\odbcHelpNetM\MSNComms32.dll

Step 5

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\odbcHelpNetM

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_SEFNIT.CY. 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:

RECOMMENDATION:

This malware is detected and removed by the latest Trend Micro anti-malware engine and pattern. Always keep pattern files and engines up-to-date. To know more about updating your Trend Micro product’s pattern, please refer to the following Trend Micro support page:

Note: The steps apply for specific products indicated in the page.
To actively detect and protect your machine, enable real-time scanning of your Trend Micro anti-malware product. Refer to the following Trend Micro support page to know more about enabling real-time scanning in your Trend Micro product:

Enable firewall to protect against threats.
http://esupport.trendmicro.com/3/How-do-I-enable-or-disable-the-Personal-Firewall-of-Trend-Micr-EN-1038273.aspx
Be aware of social engineering attacks.
Avoid accessing the listed malicious URLs to prevent possible re-infection.
Monitor network connections for any suspicious connection or connectivity.
Regularly update list of sites that are trusted.


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