TROJ_RANSOM.JG
Trojan:Win32/Tobfy.L (Microsoft); Trojan-Ransom.Win32.Blocker.aidl (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Ransomer.BJP (AVG)
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
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
39,880 bytes
EXE
Yes
10 Feb 2013
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 copies of itself into the affected system:
- %Application Data%\wmiapsvr.exe
(Note: %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.)
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\Run
wmiapsvr = "%Application Data%\wmiapsvr.exe"
Other System Modifications
This Trojan deletes the following files:
- %System Root%\r.bat
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It adds the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo
HKEY_CURRENT_USER\Software\Microsoft\
Multimedia\DrawDib
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Multimedia\DrawDib
vga.drv 1024x768x32(BGR 0) = "31,31,31,31"
Dropping Routine
This Trojan drops the following files:
- r.bat
This report is generated via an automated analysis system.
SOLUTION
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
Restart in Safe Mode
Step 3
Delete this registry key
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\SYSTEM\CurrentControlSet\Control\MediaResources
- msvideo
- In HKEY_CURRENT_USER\Software\Microsoft\Multimedia
- DrawDib
Step 4
Delete this registry value
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\Run
- wmiapsvr = "%Application Data%\wmiapsvr.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Multimedia\DrawDib
- vga.drv 1024x768x32(BGR 0) = "31,31,31,31"
Step 5
Search and delete this file
- r.bat
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_RANSOM.JG. 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 7
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.
- %System Root%\r.bat
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