arrow_back
search
close

TROJ_DROPPER.TVS

June 18, 2013
 ALIASES:

Trojan:Win32/Vundo.OD (Microsoft); Trojan.Zatvex!gen3 (Symantec); Trojan-Dropper.Win32.Cidox.jaj (Kaspersky); Trojan.Win32.Vundo.oda (v) (Sunbelt); Trojan.Vundo.GVE (FSecure)

 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:

90,112 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

13 Jun 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.

Other System Modifications

This Trojan deletes the following files:

  • %User Profile%\Cookies\index.dat
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\bottom_left3[1].png
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\bottom_right3[1].png
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\box02[1].gif
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\desktop.ini
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\top_left3[1].png
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\box04[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\box08[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\desktop.ini
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\header00b[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\table_bottom3[1].png
  • %Temporary Internet Files%\Content.IE5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\index.dat
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\background[1].gif
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\box06[1].gif
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\table_right3[1].png
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\top_right3[1].png
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\footer00[1].gif
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\table_left3[1].png
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\table_top3[1].png
  • %Temporary Internet Files%\desktop.ini

(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.. %Temporary Internet Files% is the Temporary Internet Files folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temporary Internet Files on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Microsoft\Windows\Temporary Internet Files on Windows Vista and 7.)

It deletes the following folders:

  • %Temporary Internet Files%\Content.IE5\09RWHJQN
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6
  • %Temporary Internet Files%\Content.IE5

(Note: %Temporary Internet Files% is the Temporary Internet Files folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temporary Internet Files on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Microsoft\Windows\Temporary Internet Files on Windows Vista and 7.)

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Windows
LoadAppInit_DLLs = "1"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Windows
AppInit_DLLs = "%System%\bjahfyi.dll"

Dropping Routine

This Trojan drops the following files:

  • %System%\bjahfyi.dll

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

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 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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Windows
    • LoadAppInit_DLLs = "1"

Step 3

Restore these modified registry values

[ 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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Windows
    • AppInit_DLLs = "%System%\bjahfyi.dll"

Step 4

Search and delete this file

[ Learn More ]
There may be some 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.
  • %System%\bjahfyi.dll

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_DROPPER.TVS. 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.

Step 6

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Profile%\Cookies\index.dat
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\bottom_left3[1].png
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\bottom_right3[1].png
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\box02[1].gif
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\desktop.ini
  • %Temporary Internet Files%\Content.IE5\09RWHJQN\top_left3[1].png
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\box04[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\box08[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\desktop.ini
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\header00b[1].gif
  • %Temporary Internet Files%\Content.IE5\BVLBNMKH\table_bottom3[1].png
  • %Temporary Internet Files%\Content.IE5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\index.dat
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\background[1].gif
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\box06[1].gif
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\table_right3[1].png
  • %Temporary Internet Files%\Content.IE5\ZDGZNKA5\top_right3[1].png
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\desktop.ini
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\footer00[1].gif
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\table_left3[1].png
  • %Temporary Internet Files%\Content.IE5\ZSGKJKO6\table_top3[1].png
  • %Temporary Internet Files%\desktop.ini


Did this description help? Tell us how we did.