PE_Magistr.B.Dam

June 19, 2013
 ALIASES:

Virus:Win32/Virut.BM (Microsoft); Generic.dx!ud (McAfee); W32.Virut.CF (Symantec); Virus.Win32.Virut.ce (Kaspersky); Virus.Win32.Virut.ce (v) (Sunbelt); Win32/Virut (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:

  • Threat Type: File infector

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This file infector 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:

151,552 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

14 May 2013

Arrival Details

This file infector 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 file infector creates the following folders:

  • %Windows%\fonts

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

Other System Modifications

This file infector adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{248DD896-BB45-11CF-9ABC-0080C7E7B78D}\Control

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{248DD890-BB45-11CF-9ABC-0080C7E7B78D}

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{248DD890-BB45-11CF-9ABC-0080C7E7B78D}\1.0\
0

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer\Run

HKEY_CLASSES_ROOT\csfile\DefaultIcon

HKEY_CLASSES_ROOT\csfile\shell\
open\command

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
NOHIDORSYS

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
exec = "%System%\msfeu.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Windows
run = "%System%\msdvq.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
NOHIDORSYS
CheckedValue = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Main
Use FormSuggest = "yes"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Use FormSuggest = "yes"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
DisableScriptDebuggerIE = "yes"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Error Dlg Displayed On Every Error = "no"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{248DD896-BB45-11CF-9ABC-0080C7E7B78D}\InprocServer32
ThreadingModel = "Apartment"

(Note: The default value data of the said registry entry is Apartment.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{248DD892-BB45-11CF-9ABC-0080C7E7B78D}\TypeLib
Version = "1.0"

(Note: The default value data of the said registry entry is 1.0.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{248DD893-BB45-11CF-9ABC-0080C7E7B78D}\TypeLib
Version = "1.0"

(Note: The default value data of the said registry entry is 1.0.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Windows
load = "%System%\msdsezws.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
NOHIDDEN
CheckedValue = "2"

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1601 = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Disable Script Debugger = "yes"

(Note: The default value data of the said registry entry is no.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\AeDebug
Auto = "0"

(Note: The default value data of the said registry entry is 0.)

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{248DD896-BB45-11CF-9ABC-0080C7E7B78D}

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{248DD897-BB45-11CF-9ABC-0080C7E7B78D}

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.300

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_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{248DD896-BB45-11CF-9ABC-0080C7E7B78D}
    • Control
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib
    • {248DD890-BB45-11CF-9ABC-0080C7E7B78D}
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{248DD890-BB45-11CF-9ABC-0080C7E7B78D}\1.0
    • 0
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
    • Run
  • In HKEY_CLASSES_ROOT\csfile
    • DefaultIcon
  • In HKEY_CLASSES_ROOT\csfile\shell\open
    • command
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden
    • NOHIDORSYS

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run
    • exec = "%System%\msfeu.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows
    • run = "%System%\msdvq.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\NOHIDORSYS
    • CheckedValue = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main
    • Use FormSuggest = "yes"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • Use FormSuggest = "yes"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • DisableScriptDebuggerIE = "yes"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • Error Dlg Displayed On Every Error = "no"

Step 4

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{248DD896-BB45-11CF-9ABC-0080C7E7B78D}\InprocServer32
    • From: ThreadingModel = "Apartment"
      To: ThreadingModel = ""Apartment""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{248DD892-BB45-11CF-9ABC-0080C7E7B78D}\TypeLib
    • From: Version = "1.0"
      To: Version = ""1.0""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{248DD893-BB45-11CF-9ABC-0080C7E7B78D}\TypeLib
    • From: Version = "1.0"
      To: Version = ""1.0""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows
    • load = "%System%\msdsezws.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\NOHIDDEN
    • From: CheckedValue = "2"
      To: CheckedValue = ""2""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL
    • From: CheckedValue = "0"
      To: CheckedValue = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
    • From: 1601 = "0"
      To: 1601 = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • From: Disable Script Debugger = "yes"
      To: Disable Script Debugger = ""no""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AeDebug
    • From: Auto = "0"
      To: Auto = ""0""

Step 5

Search and delete this folder

[ 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.
  • %Windows%\fonts

Step 6

Scan your computer with your Trend Micro product to clean files detected as PE_Magistr.B.Dam. 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 7

Restore these deleted registry keys/values from backup

*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
    • {248DD896-BB45-11CF-9ABC-0080C7E7B78D}
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
    • {248DD897-BB45-11CF-9ABC-0080C7E7B78D}


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