ALIASES:

TrojanDownloader:Win32/Startpage.CA (Microsoft); Downloader (Symantec); Backdoor.Win32.Trup.cs (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.5193329 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • 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: 32,768 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 23 Apr 2012

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.

Other System Modifications

This Trojan deletes the following files:

  • %System Root%\ati.exe
  • %System Root%\228.tmp
  • %Temporary Internet Files%\Content.IE5\2TPM8950\do[1].htm
  • %Temporary Internet Files%\Content.IE5\SMCZPN4M\count[1].htm
  • %Windows%\fonts\msgothic.ttf
  • %Windows%\fonts\msuigoth.ttf
  • %Windows%\fonts\MSMINCHO.TTF
  • %Windows%\fonts\Gulim.ttf
  • %Windows%\fonts\Gulimche.ttf
  • %Windows%\fonts\Dotum.ttf
  • %Windows%\fonts\Batang.ttf
  • %Windows%\fonts\Gungsuh.ttf
  • %Windows%\fonts\Simsun.ttf
  • %Windows%\fonts\nsimsun.ttf
  • %Windows%\fonts\MingLiU.ttf
  • %Windows%\fonts\pmingliu.ttf

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Temporary Internet Files% is the Temporary Internet Files folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temporary Internet Files on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Microsoft\Windows\Temporary Internet Files on Windows Vista and 7.. %Windows% is the Windows folder, which is usually C:\Windows.)

It adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Enable = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Size = "a"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
InitHits = "64"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Factor = "14"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International
W2KLpk = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International
W2KLpk = "0"

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.200

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

Delete this registry key

[ 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\Internet Explorer\International
    • CpMRU

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\Internet Explorer\International\CpMRU
    • Enable = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
    • Size = "a"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
    • InitHits = "64"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
    • Factor = "14"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
    • W2KLpk = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
    • W2KLpk = "0"

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_QUAS.SMI. 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.

Step 5

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %System Root%\ati.exe
  • %System Root%\228.tmp
  • %Temporary Internet Files%\Content.IE5\2TPM8950\do[1].htm
  • %Temporary Internet Files%\Content.IE5\SMCZPN4M\count[1].htm
  • %Windows%\fonts\msgothic.ttf
  • %Windows%\fonts\msuigoth.ttf
  • %Windows%\fonts\MSMINCHO.TTF
  • %Windows%\fonts\Gulim.ttf
  • %Windows%\fonts\Gulimche.ttf
  • %Windows%\fonts\Dotum.ttf
  • %Windows%\fonts\Batang.ttf
  • %Windows%\fonts\Gungsuh.ttf
  • %Windows%\fonts\Simsun.ttf
  • %Windows%\fonts\nsimsun.ttf
  • %Windows%\fonts\MingLiU.ttf
  • %Windows%\fonts\pmingliu.ttf


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