WORM_OTORUN.SMIF

June 25, 2013
 ALIASES:

Exploit:Win32/Siveras.E, Worm:Win32/Chiviper.C (Microsoft); Exploit-DcomRpc.g.gen (McAfee); Downloader (Symantec); Worm.Win32.AutoRun.ajkz (Kaspersky); Worm.Win32.Chiviper.c (v) (Sunbelt); Dropped:Generic.Malware.SPW.D6A4BB11 (FSecure)

 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.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size:

61,442 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

11 May 2012

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:

  • %Windows%\programs

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

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random key}
stubpath = "%windir%\programs\fuckme.vbs"

Other System Modifications

This worm adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random key}

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows Script Host\Settings

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random key}

Dropping Routine

This worm drops the following files:

  • %Windows%\programs\ini.exe
  • %Windows%\programs\desktop.ini
  • %Windows%\programs\fuckme.vbs
  • %Windows%\programs\wsock32.dll
  • \192.168.100.1\admin$\kav32.exe
  • \192.168.100.1\C$\kav32.exe
  • \192.168.100.1\D$\kav32.exe
  • \192.168.100.1\E$\kav32.exe
  • \192.168.100.1\F$\kav32.exe

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

Other Details

This worm connects to the following possibly malicious URL:

  • http://fangqi.{BLOCKED}a.cn/get.asp?mac=vPmPGGMSoL&ver=1.5

It deletes itself after execution.

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

Restart in Safe Mode

[ Learn More ]

Step 3

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\Microsoft\Active Setup\Installed Components
    • {random key}

Step 4

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\Active Setup\Installed Components\{random key}
    • stubpath = "%windir%\programs\fuckme.vbs"

Step 5

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.
  • %Windows%\programs\ini.exe
  • %Windows%\programs\desktop.ini
  • %Windows%\programs\fuckme.vbs
  • %Windows%\programs\wsock32.dll
  • \192.168.100.1\admin$\kav32.exe
  • \192.168.100.1\C$\kav32.exe
  • \192.168.100.1\D$\kav32.exe
  • \192.168.100.1\E$\kav32.exe
  • \192.168.100.1\F$\kav32.exe

Step 6

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%\programs

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_OTORUN.SMIF. 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 8

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\Microsoft\Windows Script Host
    • Settings
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {random key}


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