TROJ_LAPKA.AG


 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • 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.

  TECHNICAL DETAILS

File Size:

204,800 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 Oct 2013

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 drops the following copies of itself into the affected system:

  • %System%\wininitu.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

It creates the following folders:

  • %Windows%\LastGood
  • %Windows%\LastGood\system32
  • %Windows%\LastGood\system32\DRIVERS

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

Other System Modifications

This Trojan deletes the following files:

  • %System%\DRIVERS\SET2B.tmp
  • %Temp%\OLD28.tmp

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\diskflt

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\NetCfgLockHolder

HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Control\Network\{4d36e974-e325-11ce-bfc1-08002be10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\BITS
Fuck_Time = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wind45567 M dfg xcv 4354
Description = "Thidfg ver 1.0 fghdh"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\diskflt
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\diskflt
Start = "0"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\diskflt
Type = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\diskflt
Tag = "a"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
Characteristics = "441"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
InfPath = "%Windows%\inf\netsf.inf"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
InfSection = "Passthru.ndi"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
Description = "Passthru Driver"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
ComponentId = "ms_passthru"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\
{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
InfPath = "netsf.inf"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}
UpperFilters = "PartMgr,diskflt"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Network
Config = "{random values}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Bind = "{random characters}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Route = "{random characters}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\NdisWan\Linkage
Export = "{random characters}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008
NetCfgInstanceId = "{CA2DC9DA-D586-4464-91E8-EF8932205E21}"

(Note: The default value data of the said registry entry is {8347DFC0-2E88-4957-B577-F094C14F659F}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
RootDevice = "NdisWanIp"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
UpperBind = "Tcpip"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0008\Linkage
Export = "\Device\NdisWanIp"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0010
NetCfgInstanceId = "{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"

(Note: The default value data of the said registry entry is {3C80E3FC-D344-4CC3-8234-C304CAA58B25}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0010\Linkage
RootDevice = "{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0010\Linkage
UpperBind = "Ndisuio,RasPppoe,Tcpip"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0010\Linkage
Export = "\Device\{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001
NetCfgInstanceId = "{706C9A23-9058-4780-9179-0EE8467AACB4}"

(Note: The default value data of the said registry entry is {865B16A3-D78E-483F-8D7B-8DF6BB83FF7F}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
RootDevice = "{706C9A23-9058-4780-9179-0EE8467AACB4}"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
UpperBind = "Ndisuio,RasPppoe,Tcpip"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\
0001\Linkage
Export = "\Device\{706C9A23-9058-4780-9179-0EE8467AACB4}"

(Note: The default value data of the said registry entry is {random values}.)

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\netsf.inf
  • %System%\Black.dll
  • %User Temp%\netsf_m.inf
  • %User Temp%\snetcfg.exe
  • %User Temp%\passthru.sys
  • %Temp%\install.bat
  • %Temp%\netsf.inf
  • %Temp%\netsf_m.inf
  • %Temp%\snetcfg.exe
  • %Temp%\passthru.sys
  • %System%\Drivers\diskflt.sys
  • %Windows%\INF\netsf.PNF
  • %Windows%\inf\netsf_m.PNF
  • %Windows%\inf\INFCACHE.0
  • %Windows%\inf\netsf_m.inf
  • %Windows%\inf\netsf.inf
  • %Windows%\inf\passthru.sys
  • %System%\drivers\passthru.sys
  • %System Root%\netsf_m.inf
  • %System Root%\netsf.inf
  • %System Root%\passthru.sys
  • %Windows%\LastGood\TMP25.tmp
  • %Temp%\OLD28.tmp
  • %System%\DRIVERS\SET2B.tmp

(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.. %Windows% is the Windows folder, which is usually C:\Windows.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

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

Delete this registry key

[ Learn More ]

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\SYSTEM\ControlSet001\Services
    • diskflt
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network
    • NetCfgLockHolder
  • In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Network\{4d36e974-e325-11ce-bfc1-08002be10318}
    • {2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}

Step 3

Delete this registry value

[ Learn More ]

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\SYSTEM\ControlSet001\Services\BITS
    • Fuck_Time = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wind45567 M dfg xcv 4354
    • Description = "Thidfg ver 1.0 fghdh"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\diskflt
    • ErrorControl = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\diskflt
    • Start = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\diskflt
    • Type = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\diskflt
    • Tag = "a"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • Characteristics = "441"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • InfPath = "%Windows%\inf\netsf.inf"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • InfSection = "Passthru.ndi"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • Description = "Passthru Driver"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • ComponentId = "ms_passthru"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network\{4D36E974-E325-11CE-BFC1-08002BE10318}\{2F64EA75-FA94-4D88-9FC0-A53ABB8CDB22}
    • InfPath = "netsf.inf"

Step 4

Restore these modified registry values

[ Learn More ]

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_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}
    • From: UpperFilters = "PartMgr,diskflt"
      To: UpperFilters = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Network
    • From: Config = "{random values}"
      To: Config = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
    • From: Bind = "{random characters}"
      To: Bind = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
    • From: Route = "{random characters}"
      To: Route = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\NdisWan\Linkage
    • From: Export = "{random characters}"
      To: Export = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008
    • From: NetCfgInstanceId = "{CA2DC9DA-D586-4464-91E8-EF8932205E21}"
      To: NetCfgInstanceId = ""{8347DFC0-2E88-4957-B577-F094C14F659F}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
    • From: RootDevice = "NdisWanIp"
      To: RootDevice = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
    • From: UpperBind = "Tcpip"
      To: UpperBind = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0008\Linkage
    • From: Export = "\Device\NdisWanIp"
      To: Export = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0010
    • From: NetCfgInstanceId = "{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"
      To: NetCfgInstanceId = ""{3C80E3FC-D344-4CC3-8234-C304CAA58B25}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0010\Linkage
    • From: RootDevice = "{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"
      To: RootDevice = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0010\Linkage
    • From: UpperBind = "Ndisuio,RasPppoe,Tcpip"
      To: UpperBind = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0010\Linkage
    • From: Export = "\Device\{DAE77112-CC69-4B9B-B0BB-8B4C380B15D1}"
      To: Export = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001
    • From: NetCfgInstanceId = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
      To: NetCfgInstanceId = ""{865B16A3-D78E-483F-8D7B-8DF6BB83FF7F}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
    • From: RootDevice = "{706C9A23-9058-4780-9179-0EE8467AACB4}"
      To: RootDevice = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
    • From: UpperBind = "Ndisuio,RasPppoe,Tcpip"
      To: UpperBind = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\0001\Linkage
    • From: Export = "\Device\{706C9A23-9058-4780-9179-0EE8467AACB4}"
      To: Export = ""{random values}""

Step 5

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Temp%\netsf.inf
  • %System%\Black.dll
  • %User Temp%\netsf_m.inf
  • %User Temp%\snetcfg.exe
  • %User Temp%\passthru.sys
  • %Temp%\install.bat
  • %Temp%\netsf.inf
  • %Temp%\netsf_m.inf
  • %Temp%\snetcfg.exe
  • %Temp%\passthru.sys
  • %System%\Drivers\diskflt.sys
  • %Windows%\INF\netsf.PNF
  • %Windows%\inf\netsf_m.PNF
  • %Windows%\inf\INFCACHE.0
  • %Windows%\inf\netsf_m.inf
  • %Windows%\inf\netsf.inf
  • %Windows%\inf\passthru.sys
  • %System%\drivers\passthru.sys
  • %System Root%\netsf_m.inf
  • %System Root%\netsf.inf
  • %System Root%\passthru.sys
  • %Windows%\LastGood\TMP25.tmp
  • %Temp%\OLD28.tmp
  • %System%\DRIVERS\SET2B.tmp

Step 6

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Windows%\LastGood
  • %Windows%\LastGood\system32
  • %Windows%\LastGood\system32\DRIVERS

Step 7

Scan your computer with your Trend Micro product to delete files detected as TROJ_LAPKA.AG. 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 8

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%\DRIVERS\SET2B.tmp
  • %Temp%\OLD28.tmp


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