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TrojanSpy.MSIL.NEGASTEAL.DYSGVN

May 19, 2020
 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan Spy 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:

484,352 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

19 May 2020

Arrival Details

This Trojan Spy 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 Spy adds the following processes:

  • schtasks.exe /Create /TN "Updates\mfUkbz" /XML "%User Temp%\tmpA2C3.tmp"
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\RegSvcs.exe "{path}"
  • "netsh" wlan show profile
  • %System%\svchost.exe -k netsvcs
  • %System%\lsass.exe
  • %Windows%\Microsoft.NET\Framework\v4.0.30319\mscorsvw.exe
  • %Windows%\Microsoft.NET\Framework64\v4.0.30319\mscorsvw.exe
  • %System%\sppsvc.exe
  • "%System Root%\Program Files\Windows Media Player\wmpnetwk.exe"
  • %System%\svchost.exe -k LocalServiceAndNoImpersonation
  • taskeng.exe {922AD6D5-2D17-4DF7-B75C-522F8FA42308} S-1-5-21-2407829820-1079796033-203259571-500:{computername}\{username}:Interactive:[1]
  • %Application Data%\mfUkbz.exe %Application Data%\mfUkbz.exe
  • schtasks.exe /Create /TN "Updates\mfUkbz" /XML "%User Temp%\tmp61AF.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(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

Other System Modifications

This Trojan Spy modifies the following file(s):

  • %Windows%\Tasks\SCHEDLGU.TXT
  • %Windows%\Prefetch\SVCHOST.EXE-007FEA55.pf
  • %Windows%\Prefetch\SPPSVC.EXE-B0F8131B.pf
  • %Windows%\Prefetch\TASKENG.EXE-48D4E289.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-57D17DAF.pf
  • %Windows%\Prefetch\SEARCHPROTOCOLHOST.EXE-0CB8CADE.pf
  • %Windows%\Prefetch\CONHOST.EXE-1F3E9D7E.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-C3C515BD.pf
  • %Windows%\Prefetch\WMPNETWK.EXE-D9F2A96F.pf
  • %Windows%\Prefetch\SEARCHFILTERHOST.EXE-77482212.pf

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\VaultSvc
Type = "16"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\AeLookupSvc
Type = "16"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\LanmanServer\Shares
Users = "\x00\x00\x00\x00\x00\x00\x00"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
PolicyApplicationState
PolicyState = "0"

HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\
Microsoft\Windows\CurrentVersion\
Group Policy\PolicyApplicationState
PolicyState = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
StartTimeLo = "1927365367"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
StartTimeHi = "30788295"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
EndTimeLo = "2329537367"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
EndTimeHi = "30788295"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
Status = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\
{{GUID}}
LoggingStatus = "0"

HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\
Microsoft\Windows\CurrentVersion\
Group Policy\History
PolicyOverdue = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
StartTimeLo = "2044485367"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
StartTimeHi = "30788295"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
EndTimeLo = "2610551368"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
EndTimeHi = "30788295"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
Status = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
State\Machine\Extension-List\
{{GUID}}
LoggingStatus = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
History
PolicyOverdue = "0"

HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\
Microsoft\Windows\CurrentVersion\
Group Policy\PolicyApplicationState
PolicyState = "2"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Group Policy\
PolicyApplicationState
PolicyState = "2"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SSDPSRV
Type = "16"

(Note: The default value data of the said registry entry is 20.)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\LanmanServer\Parameters
Guid = "\x0e\xb5Ya\x1e\xabQJ\x8a\x89\x9b\x90\xeeG\x14\xc7"

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

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\LanmanServer\Parameters
Guid = "\xfe\x9e\xff\xe1Z&H\x856\xf3\xa0\xb6\xb6u\x10"

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

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
services\LanmanServer\Parameters\
Guid

Dropping Routine

This Trojan Spy drops the following files:

  • %Windows%\Tasks\SCHEDLGU.TXT
  • %Windows%\Prefetch\SVCHOST.EXE-007FEA55.pf
  • %Windows%\Prefetch\SPPSVC.EXE-B0F8131B.pf
  • %Windows%\Prefetch\TASKENG.EXE-48D4E289.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-57D17DAF.pf
  • %All Users Profile%\Microsoft\Windows\DRM\drmstore.hds
  • %Windows%\Prefetch\SEARCHPROTOCOLHOST.EXE-0CB8CADE.pf
  • %AppDataLocal%\Microsoft\Media Player\CurrentDatabase_372.wmdb
  • %Windows%\Prefetch\CONHOST.EXE-1F3E9D7E.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-C3C515BD.pf
  • %Windows%\Prefetch\SEARCHFILTERHOST.EXE-77482212.pf
  • %All Users Profile%\Microsoft\Windows\DRM\v3ks.sec
  • %System Root%\DfsServer
  • %Windows%\Prefetch\WMPNETWK.EXE-D9F2A96F.pf
  • %Application Data%\mfUkbz.exe

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). . %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.850

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Identify and terminate files detected as TrojanSpy.MSIL.NEGASTEAL.DYSGVN

[ Learn More ]
  1. 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.
  2. 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.
  3. 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

[ 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\CurrentControlSet\services\VaultSvc
    • Type = "16"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\AeLookupSvc
    • Type = "16"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Shares
    • Users = "\x00\x00\x00\x00\x00\x00\x00"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\PolicyApplicationState
    • PolicyState = "0"
  • In HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\Microsoft\Windows\CurrentVersion\Group Policy\PolicyApplicationState
    • PolicyState = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • StartTimeLo = "1927365367"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • StartTimeHi = "30788295"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • EndTimeLo = "2329537367"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • EndTimeHi = "30788295"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • Status = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\S-1-5-21-2407829820-1079796033-203259571-500\Extension-List\{{GUID}}
    • LoggingStatus = "0"
  • In HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\Microsoft\Windows\CurrentVersion\Group Policy\History
    • PolicyOverdue = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • StartTimeLo = "2044485367"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • StartTimeHi = "30788295"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • EndTimeLo = "2610551368"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • EndTimeHi = "30788295"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • Status = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Extension-List\{{GUID}}
    • LoggingStatus = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\History
    • PolicyOverdue = "0"
  • In HKEY_USERS\S-1-5-21-2407829820-1079796033-203259571-500\Software\Microsoft\Windows\CurrentVersion\Group Policy\PolicyApplicationState
    • PolicyState = "2"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\PolicyApplicationState
    • PolicyState = "2"

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\CurrentControlSet\services\SSDPSRV
    • From: Type = "16"
      To: Type = ""20""
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Parameters
    • From: Guid = "\x0e\xb5Ya\x1e\xabQJ\x8a\x89\x9b\x90\xeeG\x14\xc7"
      To: Guid = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Parameters
    • From: Guid = "\xfe\x9e\xff\xe1Z&H\x856\xf3\xa0\xb6\xb6u\x10"
      To: Guid = ""{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.
  • %Windows%\Tasks\SCHEDLGU.TXT
  • %Windows%\Prefetch\SVCHOST.EXE-007FEA55.pf
  • %Windows%\Prefetch\SPPSVC.EXE-B0F8131B.pf
  • %Windows%\Prefetch\TASKENG.EXE-48D4E289.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-57D17DAF.pf
  • %All Users Profile%\Microsoft\Windows\DRM\drmstore.hds
  • %Windows%\Prefetch\SEARCHPROTOCOLHOST.EXE-0CB8CADE.pf
  • %AppDataLocal%\Microsoft\Media Player\CurrentDatabase_372.wmdb
  • %Windows%\Prefetch\CONHOST.EXE-1F3E9D7E.pf
  • %Windows%\Prefetch\MSCORSVW.EXE-C3C515BD.pf
  • %Windows%\Prefetch\SEARCHFILTERHOST.EXE-77482212.pf
  • %All Users Profile%\Microsoft\Windows\DRM\v3ks.sec
  • %System Root%\DfsServer
  • %Windows%\Prefetch\WMPNETWK.EXE-D9F2A96F.pf
  • %Application Data%\mfUkbz.exe

Step 6

Scan your computer with your Trend Micro product to delete files detected as TrojanSpy.MSIL.NEGASTEAL.DYSGVN. 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 the following Trend Micro Support pages for more information:

Step 7

Restore deleted/modified files and/or registry entries from backup

*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

    • %Windows%\Tasks\SCHEDLGU.TXT
    • %Windows%\Prefetch\SVCHOST.EXE-007FEA55.pf
    • %Windows%\Prefetch\SPPSVC.EXE-B0F8131B.pf
    • %Windows%\Prefetch\TASKENG.EXE-48D4E289.pf
    • %Windows%\Prefetch\MSCORSVW.EXE-57D17DAF.pf
    • %Windows%\Prefetch\SEARCHPROTOCOLHOST.EXE-0CB8CADE.pf
    • %Windows%\Prefetch\CONHOST.EXE-1F3E9D7E.pf
    • %Windows%\Prefetch\MSCORSVW.EXE-C3C515BD.pf
    • %Windows%\Prefetch\WMPNETWK.EXE-D9F2A96F.pf
    • %Windows%\Prefetch\SEARCHFILTERHOST.EXE-77482212.pf

Step 8

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_LOCAL_MACHINE\SYSTEM\ControlSet001\services\LanmanServer\Parameters
    • Guid


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