TROJ_RANSOM.CMV
Trojan:Win32/Gataka.D (Microsoft); PWS-Zbot.gen.yl (McAfee); Trojan-Ransom.Win32.Birele.xxi (Kaspersky); Trojan.Win32.Generic.pak!cobra (Sunbelt)
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.
It deletes itself after execution.
TECHNICAL DETAILS
283,648 bytes
EXE
Yes
06 Apr 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 creates the following folders:
- %User Profile%\Application Data\TeamViewer
- %User Profile%\TeamViewer\{1943591E-7BE9-439E-AA9E-B3F49D5F624A}
- %User Profile%\Application Data\Windows Search
- %User Profile%\Windows Search\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}
(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.)
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
UpgradeChecker = "%User Profile%\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}\UpgradeChecker.exe"
Other System Modifications
This Trojan adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartCurrId = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartCurrMask = "3e"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartMainId = "2"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartMainMask = "7e"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
StartPage
ReserveProgram = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
PersistFile = "4"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
PersistFolder = "f"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartMenuMask = "fa8b"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
StartProcIrq = "13"
Dropping Routine
This Trojan drops the following files:
- %User Profile%\{1943591E-7BE9-439E-AA9E-B3F49D5F624A}\F532B52A6E8F49D79EF8C4E7F9887194.dat
- %User Profile%\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}\UpgradeChecker.exe
(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 Details
This Trojan deletes itself after execution.
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 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
- UpgradeChecker = "%User Profile%\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}\UpgradeChecker.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartCurrId = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartCurrMask = "3e"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartMainId = "2"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartMainMask = "7e"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\StartPage
- ReserveProgram = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- PersistFile = "4"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- PersistFolder = "f"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartMenuMask = "fa8b"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- StartProcIrq = "13"
Step 4
Search and delete these components
- %User Profile%\{1943591E-7BE9-439E-AA9E-B3F49D5F624A}\F532B52A6E8F49D79EF8C4E7F9887194.dat
- %User Profile%\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}\UpgradeChecker.exe
Step 5
Search and delete these folders
- %User Profile%\Application Data\TeamViewer
- %User Profile%\TeamViewer\{1943591E-7BE9-439E-AA9E-B3F49D5F624A}
- %User Profile%\Application Data\Windows Search
- %User Profile%\Windows Search\{A8FDD156-0553-459F-A788-C2BFDCE3AF6B}
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_RANSOM.CMV. 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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