TROJ_FAKEAV.OHC

 Analysis by: Anthony Joe Melgarejo

 ALIASES:

Rogue:Win32/Winwebsec (Microsoft), FakeAlert-SecurityTool.ga (McAfee), Troj/FakeAV-GBL (Sophos)

 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.

  TECHNICAL DETAILS

File Size:

577,024 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

09 Nov 2012

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:

  • %Start Menu%\Programs\System Progressive Protection\System Progressive Protection.lnk
  • {All User's Profile}\Application Data\{random folder name}\{random file name}
  • {All User's Profile}\Application Data\{random folder name}\{random file name}.ico
  • %Desktop%\System Progressive Protection.lnk

(Note: %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.. %Desktop% is the current user's desktop, which is usually C:\Windows\Profiles\{user name}\Desktop on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Desktop on Windows NT, and C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003.)

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

  • {All User's Profile}\Application Data\{random folder name}\{random file name}.exe

It creates the following folders:

  • %Start Menu%\Programs\System Progressive Protection
  • {All User's Profile}\Application Data\{random folder name}

(Note: %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.)

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} = "{All User's Profile}\Application Data\{random folder name}\{random file name}.exe"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Installer\Products\{random file name}

It adds the following registry entries as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
Installer\Products\{random file name}
Default = "1"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}.{BLOCKED}.29.179/api/urls/?ts={value}&affid={value}
  • http://{BLOCKED}.{BLOCKED}.29.179/api/stats/install/?ts={value}&affid={value}&ver={value}&group={value}

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

9.516.04

FIRST VSAPI PATTERN DATE:

09 Nov 2012

VSAPI OPR PATTERN File:

9.517.00

VSAPI OPR PATTERN Date:

10 Nov 2012

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

Scan your computer with your Trend Micro product and note files detected as TROJ_FAKEAV.OHC

Step 3

Restart in Safe Mode

[ Learn More ]

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
    • {random file name} = "{All User's Profile}\Application Data\{random folder name}\{random file name}.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Installer\Products\{random file name}
    • Default = "1"

Step 5

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\Microsoft\Installer\Products
    • {random file name}

Step 6

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.
  • %Start Menu%\Programs\System Progressive Protection\System Progressive Protection.lnk
  • {All User's Profile}\Application Data\{random folder name}\{random file name}
  • {All User's Profile}\Application Data\{random folder name}\{random file name}.ico
  • %Desktop%\System Progressive Protection.lnk

Step 7

Search and delete these folders

[ 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.
  • %Start Menu%\Programs\System Progressive Protection
  • {All User's Profile}\Application Data\{random folder name}

Step 8

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