PE_RAMNIT.DEN2-O
Troj/Zbot-HSJ (Sophos) ,Found Luhe.Fiha.A (AVG) ,W32/Androm.AYKE!tr.bdr (Fortinet) ,Virus.Win32.Ramnit (Ikarus) ,Backdoor.Win32.Androm.bwkg (Kaspersky) ,Trojan:Win32/Ramnit (Microsoft) ,PWSZbot-FLW!1E3B19C7BEB8 (McAfee) ,a variant of Win32/Injector.AYKE trojan (Eset) ,Generic (Panda) ,Trojan.Win32.Generic!BT (Sunbelt)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
Threat Type: File infector
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This file infector 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
581,662 bytes
EXE
Yes
06 Mar 2014
Arrival Details
This file infector 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 file infector drops the following copies of itself into the affected system:
- %User Profile%\My Documents\DCSCMIN\IMDCSC.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.)
It drops the following non-malicious file:
- %Program Files%\Internet Explorer\dmlconf.dat
(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
It creates the following folders:
- %User Profile%\Application Data\dclogs
- %User Profile%\My Documents\DCSCMIN
(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 file infector adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
DarkCometRAT = "%User Profile%\My Documents\DCSCMIN\IMDCSC.exe"
Other System Modifications
This file infector adds the following registry keys:
HKEY_CURRENT_USER\Software\DC3_FEXEC
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Program Files%\Internet Explorer\IEXPLORE.EXE = "%Program Files%\Internet Explorer\IEXPLORE.EXE:*:Enabled:internet Explorer"
File Infection
This file infector infects the following file types:
- EXE
- DLL
- HTML
Other Details
This file infector connects to the following possibly malicious URL:
- {BLOCKED}dmn.com
SOLUTION
9.700
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- DarkCometRAT = "%User Profile%\My Documents\DCSCMIN\IMDCSC.exe"
- DarkCometRAT = "%User Profile%\My Documents\DCSCMIN\IMDCSC.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %Program Files%\Internet Explorer\IEXPLORE.EXE = "%Program Files%\Internet Explorer\IEXPLORE.EXE:*:Enabled:internet Explorer"
- %Program Files%\Internet Explorer\IEXPLORE.EXE = "%Program Files%\Internet Explorer\IEXPLORE.EXE:*:Enabled:internet Explorer"
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
- DarkCometRAT = "%User Profile%\My Documents\DCSCMIN\IMDCSC.exe"
- DarkCometRAT = "%User Profile%\My Documents\DCSCMIN\IMDCSC.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %Program Files%\Internet Explorer\IEXPLORE.EXE = "%Program Files%\Internet Explorer\IEXPLORE.EXE:*:Enabled:internet Explorer"
- %Program Files%\Internet Explorer\IEXPLORE.EXE = "%Program Files%\Internet Explorer\IEXPLORE.EXE:*:Enabled:internet Explorer"
Step 5
Search and delete this folder
- %User Profile%\Application Data\dclogs
- %User Profile%\My Documents\DCSCMIN
Step 6
Search and delete this file
- %Program Files%\Internet Explorer\dmlconf.dat
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as PE_RAMNIT.DEN2-O. 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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