WORM_AUTORUN.DNM

May 31, 2013
 ALIASES:

TrojanDropper:Win32/Silly_P2P.B (Microsoft); W32/Autorun.worm.dp (McAfee); Trojan.Dropper (Symantec); Worm.Win32.AutoRun.ehw (Kaspersky); ERROR (Sunbelt); Worm/AutoRun.MH (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This worm 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:

1,244,127 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

31 May 2013

Arrival Details

This worm 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 worm creates the following folders:

  • %User Temp%\E_4

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
XP-542ADE6B = "%System%\XP-542ADE6B.EXE"

Other System Modifications

This worm deletes the following files:

  • %User Profile%\Cookies\index.dat
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\desktop.ini
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\desktop.ini
  • %Temporary Internet Files%\Content.IE5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\index.dat
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\desktop.ini
  • %Temporary Internet Files%\desktop.ini
  • %User Profile%\History.IE5\index.dat

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %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.)

It deletes the following folders:

  • %User Profile%\History\History.IE5

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Dropping Routine

This worm drops the following files:

  • %User Temp%\E_4\krnln.fnr
  • %User Temp%\E_4\shell.fne
  • %User Temp%\E_4\eAPI.fne
  • %User Temp%\E_4\internet.fne
  • %User Temp%\E_4\spec.fne
  • %User Temp%\E_4\RegEx.fnr
  • %User Temp%\E_4\dp1.fne
  • %User Temp%\E_4\com.run
  • %System%\XP-542ADE6B.EXE
  • %System%\ul.dll
  • %System%\og.dll
  • %System%\og.edt
  • %User Startup%\¡¡¡¡¡¡.lnk
  • %System%\XP-E42FD2F7.EXE
  • %System%\com.run
  • %System%\dp1.fne
  • %System%\eAPI.fne
  • %System%\internet.fne
  • %System%\krnln.fnr
  • %System%\RegEx.fnr
  • %System%\shell.fne
  • %System%\spec.fne

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

Other Details

This worm connects to the following possibly malicious URL:

  • http://www.{BLOCKED}oft.com
  • http://hi.{BLOCKED}u.com/siletoyou
  • http://hi.{BLOCKED}u.com/ul.htm
  • http://hi.{BLOCKED}u.com/au.htm

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

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • XP-542ADE6B = "%System%\XP-542ADE6B.EXE"

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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%\E_4\krnln.fnr
  • %User Temp%\E_4\shell.fne
  • %User Temp%\E_4\eAPI.fne
  • %User Temp%\E_4\internet.fne
  • %User Temp%\E_4\spec.fne
  • %User Temp%\E_4\RegEx.fnr
  • %User Temp%\E_4\dp1.fne
  • %User Temp%\E_4\com.run
  • %System%\XP-542ADE6B.EXE
  • %System%\ul.dll
  • %System%\og.dll
  • %System%\og.edt
  • %User Startup%\¡¡¡¡¡¡.lnk
  • %System%\XP-E42FD2F7.EXE
  • %System%\com.run
  • %System%\dp1.fne
  • %System%\eAPI.fne
  • %System%\internet.fne
  • %System%\krnln.fnr
  • %System%\RegEx.fnr
  • %System%\shell.fne
  • %System%\spec.fne

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.
  • %User Temp%\E_4

Step 6

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

  • %User Profile%\Cookies\index.dat
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\desktop.ini
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\desktop.ini
  • %Temporary Internet Files%\Content.IE5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\index.dat
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\desktop.ini
  • %Temporary Internet Files%\desktop.ini
  • %User Profile%\History.IE5\index.dat


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