Analysis by: Christopher Daniel So

ALIASES:

Rogue:Win32/Winwebsec (Microsoft), FakeAlert-SecurityTool.bt (McAfee)

 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.

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

  TECHNICAL DETAILS

File Size: 412,672 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 22 Nov 2011

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.

Installation

This Trojan drops the following files:

  • {malware path}\{malware file name}
  • %User Temp%\A{random hexadecimal number}.TMP.EXE

(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.)

It creates the following folders:

  • %System Root%\Documents and Settings\All Users\Application Data\CC15000HDNFN15000

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

Download Routine

This Trojan accesses the following websites to download files:

  • http://{BLOCKED}2.{BLOCKED}4.119.18/s2-1.exe?affid=15000

It saves the files it downloads using the following names:

  • %System Root%\Documents and Settings\All Users\Application Data\CC15000HDNFN15000\CC15000HDNFN15000.EXE

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

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}2.{BLOCKED}4.109.242/api/urls/?affid=15000

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 8.594.02
FIRST VSAPI PATTERN DATE: 23 Nov 2011

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Search and delete these files

[ Learn More ]
There may be some component files 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.
  • {malware path}\{malware file name}
  • %User Temp%\A{random hexadecimal number}.TMP.EXE

Step 3

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.
  • %System Root%\Documents and Settings\All Users\Application Data\CC15000HDNFN15000

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_FAKEAV.EJL. 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.


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