ALIASES:

PWS:Win32/Fareit.gen!C (Microsoft); PWS-Zbot.gen.ad (McAfee); Trojan Horse (Symantec); Trojan-PSW.Win32.Tepfer.hztn (Kaspersky); Trojan.Win32.Zbocheman.fb (v) (Sunbelt); Trojan horse PSW.Generic11.BSW (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This spyware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size: 97,280 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 11 May 2013

Arrival Details

This spyware 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 spyware creates the following folders:

  • %User Profile%\Application Data\Nyri

(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.)

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\WinRAR

HKEY_CURRENT_USER\Software\Microsoft\
Okseyd

HKEY_LOCAL_MACHINE\Software\Google\
Chrome\Extensions

It adds the following registry entries:

HKEY_CURRENT_USER\Software\WinRAR
HWID = "{random values}"

HKEY_CURRENT_USER\Software\WinRAR
Client Hash = "{random values}"

HKEY_CURRENT_USER\Software\WinRAR
1FDA774E3DA42B8517F40D91B95569A7 = "{random values}"

HKEY_CURRENT_USER\Software\WinRAR
BE451704D4347D4DA9FCA065BD53F3DB = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Okseyd
32321h4i = "hwgsVewaefoDjoUy?_CHAR(0x05)_?"

Dropping Routine

This spyware drops the following files:

  • %User Temp%\41515.exe
  • %User Temp%\47531.exe
  • %User Profile%\Application Data\Nyri
  • %User Profile%\Nyri\lodev.exe
  • %Application Data%\iwekji.qec
  • %User Profile%\Application Data\mayui.dll

(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %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.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

Other Details

This spyware connects to the following possibly malicious URL:

  • http://{BLOCKED}.131.158/{random path}

It deletes itself after execution.

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
    • WinRAR
  • In HKEY_CURRENT_USER\Software\Microsoft
    • Okseyd
  • In HKEY_LOCAL_MACHINE\Software\Google\Chrome
    • Extensions

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\WinRAR
    • HWID = "{random values}"
  • In HKEY_CURRENT_USER\Software\WinRAR
    • Client Hash = "{random values}"
  • In HKEY_CURRENT_USER\Software\WinRAR
    • 1FDA774E3DA42B8517F40D91B95569A7 = "{random values}"
  • In HKEY_CURRENT_USER\Software\WinRAR
    • BE451704D4347D4DA9FCA065BD53F3DB = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Okseyd
    • 32321h4i = "hwgsVewaefoDjoUy?_CHAR(0x05)_?"

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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.
  • %User Temp%\41515.exe
  • %User Temp%\47531.exe
  • %User Profile%\Application Data\Nyri
  • %User Profile%\Nyri\lodev.exe
  • %Application Data%\iwekji.qec
  • %User Profile%\Application Data\mayui.dll

Step 5

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.
  • %User Profile%\Application Data\Nyri

Step 6

Scan your computer with your Trend Micro product to delete files detected as TSPY_TEPFER.ASL. 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.