BKDR_BIFROSE.TAF
Backdoor:Win32/Bifrose.EY (MIcrosoft); Trojan Horse (Symantec)
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This backdoor 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
85,373 bytes
EXE
Yes
24 Jun 2010
Arrival Details
This backdoor 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 backdoor drops the following files:
- %System%\Systems.exe\klog.dat
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
It drops the following copies of itself into the affected system:
- %System%\Systems.exe\usnsvcc.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
It creates the following folders:
- %System%\Systems.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{9B71D88C-C598-4935-C5D1-43AA4DB90836}
stubpath = "%System%\Systems.exe\usnsvcc.exe s"
Other System Modifications
This backdoor adds the following registry keys as part of its installation routine:
HKEY_CURRENT_USER\Software\Bifrost
HKEY_LOCAL_MACHINE\SOFTWARE\Bifrost
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{9B71D88C-C598-4935-C5D1-43AA4DB90836}
Other Details
This backdoor connects to the following possibly malicious URL:
- {BLOCKED}pname.no-ip.org
SOLUTION
9.200
7.262.15
24 Jun 2010
7.263.00
24 Jun 2010
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_CURRENT_USER\Software
- Bifrost
- Bifrost
- In HKEY_LOCAL_MACHINE\SOFTWARE
- Bifrost
- Bifrost
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
- {9B71D88C-C598-4935-C5D1-43AA4DB90836}
- {9B71D88C-C598-4935-C5D1-43AA4DB90836}
Step 4
Search and delete these folders
- %System%\Systems.exe
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_BIFROSE.TAF. 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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