BKDR_DEMTRANC.AF
a variant of Win32/Demtranc.AA trojan (Eset), Trojan.Renos (Ikarus), Generic.grp!gz (McAfee)
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: Backdoor
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Dropped by other malware
This backdoor may be dropped by other malware.
It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.
It retrieves specific information from the affected system.
TECHNICAL DETAILS
95,744 bytes
Yes
06 Mar 2012
Collects system information, Connects to URLs/IPs
Arrival Details
This backdoor may be dropped by other malware.
Installation
This backdoor drops the following file(s)/component(s):
- %Application Data%\Microsoft\plugin_containor.exe - also detected as BKDR_DEMTRANC.AF
(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 backdoor creates the following registry entries to enable automatic execution of dropped component at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Plugin Container = "%Application Data%\Microsoft\plugin_containor.exe"
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Terminate Itself (exit)
- Download File (put)
- Idle (sleep)
- Remote Command Line Execution (dos)
- Execute File (run)
It connects to the following websites to send and receive information:
- {BLOCKED}i.{BLOCKED}S.biz/SEU{value}O{value}.jsp?{value}
- {BLOCKED}i.{BLOCKED}S.biz/SUS{value}O{value}.jsp?{value}
- {BLOCKED}i.{BLOCKED}S.biz/ZES{value}O{value}.jsp?{value}
- {BLOCKED}i.{BLOCKED}S.biz/AES{value}O{value}.jsp?{value}
- {BLOCKED}i.{BLOCKED}S.biz/DES{value}O{value}.jsp?{value}
Information Theft
This backdoor retrieves the following information from the affected system:
- Username
- Hostname
- OS Version
- IP Address
SOLUTION
9.300
8.824.04
06 Mar 2012
8.825.00
07 Mar 2012
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
Identify and terminate files detected as BKDR_DEMTRANC.AF
- Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
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
- Plugin Container = "%Application Data%\Microsoft\plugin_containor.exe"
- Plugin Container = "%Application Data%\Microsoft\plugin_containor.exe"
Step 4
Scan your computer with your Trend Micro product to delete files detected as BKDR_DEMTRANC.AF 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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