TROJ_DROPER.SMJN
TrojanDropper:Win32/Hupigon.gen!A (Microsoft); [00236a68.EXE]:BackDoor-ALC, [00004a68.EXE]:generic!bg.hhm (McAfee); PAK:PE_Patch, Trojan-Dropper.Win32.Agent.lr (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Dropper.Delf.LR (FSecure)
Windows 2000, Windows XP, Windows Server 2003
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
2,628,096 bytes
EXE
No
18 Apr 2012
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 Temp%\dat
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)
Other System Modifications
This Trojan deletes the following files:
- %System Root%\clear.bat
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
cFormatTags = "3"
(Note: The default value data of the said registry entry is 3.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
cFormatTags = "3"
(Note: The default value data of the said registry entry is 3.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
cFilterTags = "0"
Dropping Routine
This Trojan drops the following files:
- %System%\flash.dat
- %System%\mmm.dat
- %System%\runf.bat
- clear.bat
- %User Temp%\EXE_temp0.exe
- %User Temp%\EXE_temp1.exe
- %Windows%\TXPlatform.exe
- {malware path and file name}
(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.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
Other Details
This Trojan deletes itself after execution.
This report is generated via an automated analysis system.
SOLUTION
9.200
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
Restore this modified 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_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: cFormatTags = "3"
To: cFormatTags = ""3""
- From: cFormatTags = "3"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: cFormatTags = "3"
To: cFormatTags = ""3""
- From: cFormatTags = "3"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- cFilterTags = "0"
Step 3
Search and delete these files
- %System%\flash.dat
- %System%\mmm.dat
- %System%\runf.bat
- clear.bat
- %User Temp%\EXE_temp0.exe
- %User Temp%\EXE_temp1.exe
- %Windows%\TXPlatform.exe
- {malware path and file name}
Step 4
Search and delete this folder
- %User Temp%\dat
Step 5
Scan your computer with your Trend Micro product to delete files detected as TROJ_DROPER.SMJN. 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 6
Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.
- %System Root%\clear.bat
Did this description help? Tell us how we did.