TROJ_FAKEAV.HBO

April 13, 2011
 Analysis by: Christopher Daniel So
 ALIASES:

FakeAlert-SecurityTool.br (McAfee)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Trojan adds registry entries to enable its automatic execution at every system startup.

It displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

02 Apr 2011

Payload:

Displays graphics/image, Connects to URLs/Ips

Installation

This Trojan drops the following copies of itself into the affected system:

  • %System Root%\Documents and Settings\All Users\Application Data\{random folder}\{random file name}.exe

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

It drops the following files:

  • %System Root%\Documents and Settings\All Users\Application Data\{random folder}\{random file name}

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

It creates the following folders:

  • %System Root%\Documents and Settings\All Users\Application Data\{random folder}

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

It terminates the execution of the copy it initially executed and executes the copy it drops instead.

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
{random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random folder}\{random file name}.exe"

Other Details

This Trojan displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.

NOTES:

It connects to the following URL to remotely inform a malicious user of its installation:

  • http://{BLOCKED}9.{BLOCKED}0.195.76/i.php?{random characters}

It displays the following window and pretends to scan the system:

It displays the following summary window leaving the user the option to remove all threats:

If the user chooses to remove the threats, it displays the following window:

If the user agrees to activate the software, the user is redirected to the following page:

It sends gathered information to the following URL via HTTP POST:

  • http://{BLOCKED}9.{BLOCKED}0.209.220/b.php

It also prevents applications from executing:

  SOLUTION

Minimum Scan Engine:

8.900

FIRST VSAPI PATTERN FILE:

7.950.02

FIRST VSAPI PATTERN DATE:

04 Apr 2011

VSAPI OPR PATTERN File:

7.951.00

VSAPI OPR PATTERN Date:

05 Apr 2011

Step 1

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

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
    • {random file name}="%System Root%\Documents and Settings\All Users\Application Data\{random folder}\{random file name}.exe"

Step 4

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\{random folder}

Step 5

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