BKDR_POISON.DAS
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted:
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
212,320 bytes
EXE
No
14 Aug 2013
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.
Other System Modifications
This backdoor modifies the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer
FaultCount = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer
FaultTime = "e6e5"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer
FaultCount = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer
FaultTime = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer
CleanShutdown = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
SysTray
Services = "1f"
(Note: The default value data of the said registry entry is 1f.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Tracing\
Microsoft\Imapi
LogSessionName = "stdout"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Tracing\
Microsoft\Imapi
Active = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Tracing\
Microsoft\Imapi
ControlFlags = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Tracing\
Microsoft\Imapi\ImapiSvc
Guid = "8107d8e9-e323-49f5-bba2-abc35c243dca"
(Note: The default value data of the said registry entry is 8107d8e9-e323-49f5-bba2-abc35c243dca.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Tracing\
Microsoft\Imapi\ImapiSvc
BitNames = "{random characters}"
(Note: The default value data of the said registry entry is ImapiDebugError ImapiDebugWarning ImapiDebugTrace ImapiDebugInfo ImapiDebugX ImapiDebugSort.)
It deletes the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
IEAK\GroupPolicy\PendingGPOs
Dropping Routine
This backdoor drops the following files:
- %System%\memshare.dat
- %Windows%\ntshrui.dll
- %Temp%\6mebwk9p.TMP
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %Windows% is the Windows folder, which is usually C:\Windows.. %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)
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
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
- FaultCount = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
- FaultTime = "e6e5"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
- FaultCount = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
- FaultTime = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
- CleanShutdown = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\SysTray
- From: Services = "1f"
To: Services = ""1f""
- From: Services = "1f"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\Microsoft\Imapi
- From: LogSessionName = "stdout"
To: LogSessionName = ""{random values}""
- From: LogSessionName = "stdout"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\Microsoft\Imapi
- From: Active = "1"
To: Active = ""1""
- From: Active = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\Microsoft\Imapi
- From: ControlFlags = "1"
To: ControlFlags = ""1""
- From: ControlFlags = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\Microsoft\Imapi\ImapiSvc
- From: Guid = "8107d8e9-e323-49f5-bba2-abc35c243dca"
To: Guid = ""8107d8e9-e323-49f5-bba2-abc35c243dca""
- From: Guid = "8107d8e9-e323-49f5-bba2-abc35c243dca"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\Microsoft\Imapi\ImapiSvc
- From: BitNames = "{random characters}"
To: BitNames = "" ImapiDebugError ImapiDebugWarning ImapiDebugTrace ImapiDebugInfo ImapiDebugX ImapiDebugSort""
- From: BitNames = "{random characters}"
Step 3
Search and delete these components
- %System%\memshare.dat
- %Windows%\ntshrui.dll
- %Temp%\6mebwk9p.TMP
Step 4
Scan your computer with your Trend Micro product to delete files detected as BKDR_POISON.DAS. 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 5
Restore these deleted registry keys/values from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- In HKEY_CURRENT_USER\Software\Microsoft\IEAK\GroupPolicy
- PendingGPOs
Did this description help? Tell us how we did.