TROJ_SMALL.MTD

October 09, 2012
 Analysis by: Kathleen Notario
 ALIASES:

TrojanDownloader:Win32/Karagany.G (Microsoft)

 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 arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size:

14,848 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

25 Nov 2011

Payload:

Connects to URLs/IPs, Downloads files

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan adds the following mutexes to ensure that only one of its copies runs at any one time:

  • yUo9Ck1Io

NOTES:

It will check If the process notepad.exe is running on the affected system. It will then inject codes into the said process.

It accesses the following URL:

  • http://{BLOCKED}fc.{BLOCKED}a.pl/showthread.php?t=142286
The said URL redirects to:
  • http://www.{BLOCKED}e.pl/index.html

It then downloads the said page and saves an encrypted form of it as %User Temp%\{random filename}. This file has been verified as non-malicious.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

8.600.07

FIRST VSAPI PATTERN DATE:

25 Nov 2011

VSAPI OPR PATTERN File:

8.601.00

VSAPI OPR PATTERN Date:

26 Nov 2011

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

Identify and terminate files detected as TROJ_SMALL.MTD

[ Learn More ]
  1. 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.
  2. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

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.
  •  %User Temp%\{random filename}

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_SMALL.MTD. 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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