WORM_SILLY.AT


 ALIASES:

Worm:Win32/Delf.AH (Microsoft); W32/Generic.Delphi.a (McAfee); W32.SillyP2P (Symantec); P2P-Worm.Win32.Small.t (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Worm/Generic.EI (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:

461,801 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 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 drops the following copies of itself into the affected system:

  • \incoming\{malware file name}
  • \edonkey2000 downloads\{malware file name}
  • %systemdrive%\documents and settings\my documents\morpheus shared\downloads\{malware file name}
  • %User Profile%\my music\{malware file name}
  • \{malware file name}
  • %System Root%\my doswnloads\{malware file name}

(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.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

Other System Modifications

This worm adds the following registry keys:

HKEY_CURRENT_USER\Software\eMule

HKEY_CURRENT_USER\Software\Kazaa\
LocalContent

HKEY_CURRENT_USER\Software\iMesh\
iMesh5\Transfer

HKEY_CURRENT_USER\Software\Shareaza\
Shareaza\Downloads

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Start Page = "http://www.{BLOCKED}irefox.dl.am"

(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome.)

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_CURRENT_USER\Software
    • eMule
  • In HKEY_CURRENT_USER\Software\Kazaa
    • LocalContent
  • In HKEY_CURRENT_USER\Software\iMesh\iMesh5
    • Transfer
  • In HKEY_CURRENT_USER\Software\Shareaza\Shareaza
    • Downloads

Step 3

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_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • From: Start Page = "http://www.{BLOCKED}irefox.dl.am"
      To: Start Page = ""http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome""

Step 4

Scan your computer with your Trend Micro product to delete files detected as WORM_SILLY.AT. 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.


Did this description help? Tell us how we did.