Analysis by: Roland Dela Paz
ALIASES:

Trojan.FakeAV (Symantec); Mal/FakeAV-JS (Sophos)

 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 may be downloaded by other malware/grayware/spyware from remote sites. It may be unknowingly downloaded by a user while visiting malicious websites.

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

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 365,568 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 06 Apr 2011
Payload: Compromises system security

Arrival Details

This Trojan may be downloaded by other malware/grayware/spyware from remote sites.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

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

  • %System Root%\Documents and Settings\All Users\Application Data\{random}\{random}.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 non-malicious file:

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

(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}

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

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} = "%System Root%\Documents and Settings\All Users\Application Data\{random}\{random}.exe"

Other Details

This Trojan connects to the following website to send and receive information:

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

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.954.02
FIRST VSAPI PATTERN DATE: 06 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

Identify and terminate files detected as TROJ_FAKEAV.RJS

[ Learn More ]
  1. For Windows 98 and ME users, Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

Delete this registry value

[ 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\Windows\CurrentVersion\RunOnce
    • {random} = "%System Root%\Documents and Settings\All Users\Application Data\{random}\{random}.exe"

Step 5

Scan your computer with your Trend Micro product to delete files detected as MALWARE_FILE

*Note: If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further steps are required. You may opt to simply delete the quarantined files. Please check out this Knowledge Base page for more information.


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