BKDR_EMBED.GG

October 12, 2012
 ALIASES:

ERROR (Sunbelt)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • 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.

It modifies files, disabling programs and applications from properly running.

  TECHNICAL DETAILS

File Size:

3,229,236 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

04 May 2012

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 creates the following folders:

  • %System Root%\MSIc8e96.tmp
  • %System Root%\Config.Msi
  • %Program Files%\LogMeIn Hamachi

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Program Files% is the default Program Files folder, usually C:\Program Files.)

Other System Modifications

This backdoor modifies the following files:

  • %System%\c_863.nls

(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 deletes the following files:

  • %User Temp%\MSI2.tmp
  • %User Temp%\MSI3.tmp
  • %User Temp%\MSI4.tmp
  • %User Temp%\MSI5.tmp
  • %User Temp%\MSI6.tmp
  • %Windows%\Installer\MSI7.tmp
  • %System Root%\Config.Msi\MSI9.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.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It deletes the following folders:

  • %User Profile%\My Documents\My Pictures
  • %Start Menu%\Programs\Administrative Tools

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Installer\
InProgress

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Installer\
Rollback\Scripts

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
10762A243D001A84B8AC7C9E48DD2EF9

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
F0C57D3D80247CD4A85444A9A4CEB1AB

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
87464FE8845CB0146BEC679A0AECCF69

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
0D68A5EF63FA8784CA65D24AF49A3924

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
9A358216EA4E6D44A90C656175D7F770

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
9F6D55C0455B62D4DA628DCC3CFA49DA

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
FC803EDD55EEDD24BA086AE97868E14C

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
1B6669ADCADF9CB40B18EB51784545FF

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
73041C560C0E04741873C67A0CF9B069

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
B899F0D8ABB0BE84292818EE52F41737

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
Rollback\Scripts
%System Root%\Config.Msi\dd64e3.rbs = "4a3a9a"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
10762A243D001A84B8AC7C9E48DD2EF9
AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi.sys"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
F0C57D3D80247CD4A85444A9A4CEB1AB
AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi-2.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
9A358216EA4E6D44A90C656175D7F770
AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi-2-ui.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
9F6D55C0455B62D4DA628DCC3CFA49DA
AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi.lng"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
FC803EDD55EEDD24BA086AE97868E14C
AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\license.rtf"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
73041C560C0E04741873C67A0CF9B069
AABFD194FE7760B46867F26CE6EE40A9 = "%Start Menu%\Programs\LogMeIn Hamachi"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Installer\
UserData\S-1-5-18\Components\
B899F0D8ABB0BE84292818EE52F41737
AABFD194FE7760B46867F26CE6EE40A9 = "{random characters}"

Dropping Routine

This backdoor drops the following files:

  • %User Temp%\hamachi.msi
  • %User Temp%\ADMIN18.exe
  • %User Temp%\dc8e95.msi
  • %Windows%\Installer\dd64e1.msi
  • %Windows%\Installer\dd64e2.ipi
  • %Windows%\Installer\MSI8.tmp
  • %System Root%\Config.Msi\dd64e3.rbs

(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.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %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:

9.200

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

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\Software\Microsoft\Windows\CurrentVersion\Installer
    • InProgress
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Installer\Rollback
    • Scripts
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 10762A243D001A84B8AC7C9E48DD2EF9
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • F0C57D3D80247CD4A85444A9A4CEB1AB
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 87464FE8845CB0146BEC679A0AECCF69
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 0D68A5EF63FA8784CA65D24AF49A3924
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 9A358216EA4E6D44A90C656175D7F770
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 9F6D55C0455B62D4DA628DCC3CFA49DA
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • FC803EDD55EEDD24BA086AE97868E14C
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 1B6669ADCADF9CB40B18EB51784545FF
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • 73041C560C0E04741873C67A0CF9B069
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components
    • B899F0D8ABB0BE84292818EE52F41737

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\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\Rollback\Scripts
    • %System Root%\Config.Msi\dd64e3.rbs = "4a3a9a"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\10762A243D001A84B8AC7C9E48DD2EF9
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi.sys"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\F0C57D3D80247CD4A85444A9A4CEB1AB
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi-2.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\9A358216EA4E6D44A90C656175D7F770
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi-2-ui.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\9F6D55C0455B62D4DA628DCC3CFA49DA
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\hamachi.lng"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\FC803EDD55EEDD24BA086AE97868E14C
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Program Files%\LogMeIn Hamachi\license.rtf"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\73041C560C0E04741873C67A0CF9B069
    • AABFD194FE7760B46867F26CE6EE40A9 = "%Start Menu%\Programs\LogMeIn Hamachi"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\B899F0D8ABB0BE84292818EE52F41737
    • AABFD194FE7760B46867F26CE6EE40A9 = "{random characters}"

Step 4

Search and delete these files

[ Learn More ]
There may be some component files 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%\hamachi.msi
  • %User Temp%\ADMIN18.exe
  • %User Temp%\dc8e95.msi
  • %Windows%\Installer\dd64e1.msi
  • %Windows%\Installer\dd64e2.ipi
  • %Windows%\Installer\MSI8.tmp
  • %System Root%\Config.Msi\dd64e3.rbs

Step 5

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.
  • %System Root%\MSIc8e96.tmp
  • %System Root%\Config.Msi
  • %Program Files%\LogMeIn Hamachi

Step 6

Scan your computer with your Trend Micro product to delete files detected as BKDR_EMBED.GG. 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 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.

    • %System%\c_863.nls

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.

  • %User Temp%\MSI2.tmp
  • %User Temp%\MSI3.tmp
  • %User Temp%\MSI4.tmp
  • %User Temp%\MSI5.tmp
  • %User Temp%\MSI6.tmp
  • %Windows%\Installer\MSI7.tmp
  • %System Root%\Config.Msi\MSI9.tmp


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