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.

  TECHNICAL DETAILS

File Size: 488,186 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 22 Nov 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 deletes the following files:

  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\XRegistry.bin

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It adds the following registry keys:

HKEY_CURRENT_USER\Software\Xenocode

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2\Virtual

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2\Virtual\
MODIFIED

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2\Virtual\
MODIFIED\@HKLM@

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2\Virtual\
MODIFIED\@HKCR@

HKEY_CURRENT_USER\Software\Xenocode\
SandboxCache\2BEF1AB2\Virtual\
MODIFIED\@HKCR@\CLSID

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\{d94104a5-f82c-11e0-a858-806d6172696f}
BaseClass = "Drive"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\{d94104a2-f82c-11e0-a858-806d6172696f}
BaseClass = "Drive"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\ShellNoRoam\MUICache
%System Root%\2.exe = "-656599454"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
MountPoints2\D
BaseClass = "Drive"

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Personal = "%User Profile%\My Documents"

(Note: The default value data of the said registry entry is %User Profile%\My Documents.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Common Documents = "%User Profile%\Documents"

(Note: The default value data of the said registry entry is %System Root%\Documents and Settings\All Users\Documents.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Desktop = "%Desktop%"

(Note: The default value data of the said registry entry is %User Profile%\Desktop.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Common Desktop = "%Desktop%"

(Note: The default value data of the said registry entry is %System Root%\Documents and Settings\All Users\Desktop.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
ProxyBypass = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
IntranetName = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
ZoneMap
UNCAsIntranet = "1"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Cache = "%Temporary Internet Files%"

(Note: The default value data of the said registry entry is %User Profile%\Local Settings\Temporary Internet Files.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Shell Folders
Cookies = "%User Profile%\Cookies"

(Note: The default value data of the said registry entry is %User Profile%\Cookies.)

Dropping Routine

This backdoor drops the following files:

  • %Application Data%\Xenocode
  • %Application Data%\Xenocode\Sandbox
  • %Application Data%\Xenocode\Sandbox\-326626514
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE\@APPDIR@
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE\@APPDIR@\2.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

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_CURRENT_USER\Software
    • Xenocode
  • In HKEY_CURRENT_USER\Software\Xenocode
    • SandboxCache
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache
    • 2BEF1AB2
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache\2BEF1AB2
    • Virtual
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache\2BEF1AB2\Virtual
    • MODIFIED
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache\2BEF1AB2\Virtual\MODIFIED
    • @HKLM@
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache\2BEF1AB2\Virtual\MODIFIED
    • @HKCR@
  • In HKEY_CURRENT_USER\Software\Xenocode\SandboxCache\2BEF1AB2\Virtual\MODIFIED\@HKCR@
    • CLSID

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{d94104a5-f82c-11e0-a858-806d6172696f}
    • BaseClass = "Drive"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{d94104a2-f82c-11e0-a858-806d6172696f}
    • BaseClass = "Drive"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\ShellNoRoam\MUICache
    • %System Root%\2.exe = "-656599454"

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\D
    • From: BaseClass = "Drive"
      To: BaseClass = ""Drive""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Personal = "%User Profile%\My Documents"
      To: Personal = ""%User Profile%\My Documents""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Common Documents = "%User Profile%\Documents"
      To: Common Documents = ""%System Root%\Documents and Settings\All Users\Documents""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Desktop = "%Desktop%"
      To: Desktop = ""%User Profile%\Desktop""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Common Desktop = "%Desktop%"
      To: Common Desktop = ""%System Root%\Documents and Settings\All Users\Desktop""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: ProxyBypass = "1"
      To: ProxyBypass = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: IntranetName = "1"
      To: IntranetName = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap
    • From: UNCAsIntranet = "1"
      To: UNCAsIntranet = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Cache = "%Temporary Internet Files%"
      To: Cache = ""%User Profile%\Local Settings\Temporary Internet Files""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
    • From: Cookies = "%User Profile%\Cookies"
      To: Cookies = ""%User Profile%\Cookies""

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.
  • %Application Data%\Xenocode
  • %Application Data%\Xenocode\Sandbox
  • %Application Data%\Xenocode\Sandbox\-326626514
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE\@APPDIR@
  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\STUBEXE\@APPDIR@\2.exe

Step 6

Scan your computer with your Trend Micro product to delete files detected as BKDR_BIFROSE.GDN. 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 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.

  • %Application Data%\Xenocode\Sandbox\-326626514\-251694984625\1433.08.07T01.19\Virtual\XRegistry.bin


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