PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Adware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This adware 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

File Size: 3,385,344 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 17 Mar 2014

Arrival Details

This adware 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 adware creates the following folders:

  • %Program Files%\Browsersafeguard
  • %Program Files%\Browsersafeguard\Resources
  • %Start Menu%\Programs\BrowserSafeguard

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu on Windows Vista and 7.)

Autostart Technique

This adware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
BrowserSafeguard = "%Program Files%\Browsersafeguard\BrowserSafeguard.exe "

Other System Modifications

This adware modifies the following file(s):

  • %Application Data%\GDIPFONTCACHEV1.DAT
  • %User Profile%\Application Data\Microsoft

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

It deletes the following files:

  • %Windows%\Tasks\Temp{1cba5f87-9fd8-4fe4-b0f1-3ee0156e3ef4}.job
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\security.config.cch.428.181843
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\enterprisesec.config.cch.428.181843
  • %User Profile%\v2.0.50727.42\security.config.cch.428.181984

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

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\ROOT\Certificates\
B3BE3312DAAE1AEC57984BDFE1DDCDF5321EA527

HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard

HKEY_CURRENT_USER\SOFTWARE\BrowsersafeguardInstalled

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
ESENT\Process\BrowserSafeguard

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
ESENT\Process\BrowserSafeguard\
DEBUG

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
FiddlerCore\Dynamic

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
InstallDate = "20140211"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
DisplayName = "BrowserSafeguard"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
DisplayIcon = "%Program Files%\Browsersafeguard\uninstall.BrowserSafeguard.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
Publisher = "Browsersafeguard"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
InstallLocation = "%Program Files%\Browsersafeguard"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
UninstallString = "{random characters}"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
Browsersafeguard
EstimatedSize = "12c"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\ROOT\Certificates\
B3BE3312DAAE1AEC57984BDFE1DDCDF5321EA527
Blob = "{random values}"

HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
userid = "47d7f250-5fad-41a8-8f6c-95d641b93410"

HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
uc = "20140313"

HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
implementationid = "browsersafeguard-dl"

HKEY_CURRENT_USER\Software\Microsoft\
FiddlerCore\Dynamic
Attached = "1"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
GDIPlus
FontCachePath = "%Application Data%"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
EventMessageFile = "%System%\ESENT.dll"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryMessageFile = "%System%\ESENT.dll"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryCount = "1"

(Note: The default value data of the said registry entry is 10.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
TypesSupported = "7"

(Note: The default value data of the said registry entry is 7.)

Dropping Routine

This adware drops the following files:

  • %User Temp%\System.Data.SQLite.dll
  • %Program Files%\52773ce2-c582-42da-a973-61c8028a61e0.tmp
  • %Program Files%\Browsersafeguard\BrowserSafeguard.exe.tmp
  • %Program Files%\Browsersafeguard\ewebstorewrapper.dll.tmp
  • %Program Files%\Browsersafeguard\makecert.exe.tmp
  • %Program Files%\Browsersafeguard\Resources\certutil.exe.tmp
  • %Program Files%\Browsersafeguard\Resources\libnspr4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\libplc4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\libplds4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\nss3.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\smime3.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\softokn3.dll.tmp
  • %Start Menu%\Programs\BrowserSafeguard\BrowserSafeguard.lnk
  • %Program Files%\Browsersafeguard\uninstall.BrowserSafeguard.exe
  • %Windows%\Tasks\BrowserSafeguard Update Task.job
  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-1645522239-1292428093-682003330-1003
  • %Program Files%\Browsersafeguard\TrustedRoot.cer

(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.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu on Windows Vista and 7.. %Windows% is the Windows folder, which is usually C:\Windows.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other Details

This adware deletes itself after execution.

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

Restart in Safe Mode

[ Learn More ]

Step 3

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\Uninstall
    • Browsersafeguard
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\ROOT\Certificates
    • B3BE3312DAAE1AEC57984BDFE1DDCDF5321EA527
  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • Browsersafeguard
  • In HKEY_CURRENT_USER\SOFTWARE
    • BrowsersafeguardInstalled
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ESENT\Process
    • BrowserSafeguard
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ESENT\Process\BrowserSafeguard
    • DEBUG
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\FiddlerCore
    • Dynamic

Step 4

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\Run
    • BrowserSafeguard = "%Program Files%\Browsersafeguard\BrowserSafeguard.exe "
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • InstallDate = "20140211"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • DisplayName = "BrowserSafeguard"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • DisplayIcon = "%Program Files%\Browsersafeguard\uninstall.BrowserSafeguard.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • Publisher = "Browsersafeguard"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • InstallLocation = "%Program Files%\Browsersafeguard"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • UninstallString = "{random characters}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Browsersafeguard
    • EstimatedSize = "12c"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\ROOT\Certificates\B3BE3312DAAE1AEC57984BDFE1DDCDF5321EA527
    • Blob = "{random values}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
    • userid = "47d7f250-5fad-41a8-8f6c-95d641b93410"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
    • uc = "20140313"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Browsersafeguard
    • implementationid = "browsersafeguard-dl"
  • In HKEY_CURRENT_USER\Software\Microsoft\FiddlerCore\Dynamic
    • Attached = "1"

Step 5

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\GDIPlus
    • From: FontCachePath = "%Application Data%"
      To: FontCachePath = ""%User Profile%\Local Settings\Application Data""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: EventMessageFile = "%System%\ESENT.dll"
      To: EventMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryMessageFile = "%System%\ESENT.dll"
      To: CategoryMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryCount = "1"
      To: CategoryCount = ""10""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: TypesSupported = "7"
      To: TypesSupported = ""7""

Step 6

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%\System.Data.SQLite.dll
  • %Program Files%\52773ce2-c582-42da-a973-61c8028a61e0.tmp
  • %Program Files%\Browsersafeguard\BrowserSafeguard.exe.tmp
  • %Program Files%\Browsersafeguard\ewebstorewrapper.dll.tmp
  • %Program Files%\Browsersafeguard\makecert.exe.tmp
  • %Program Files%\Browsersafeguard\Resources\certutil.exe.tmp
  • %Program Files%\Browsersafeguard\Resources\libnspr4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\libplc4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\libplds4.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\nss3.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\smime3.dll.tmp
  • %Program Files%\Browsersafeguard\Resources\softokn3.dll.tmp
  • %Start Menu%\Programs\BrowserSafeguard\BrowserSafeguard.lnk
  • %Program Files%\Browsersafeguard\uninstall.BrowserSafeguard.exe
  • %Windows%\Tasks\BrowserSafeguard Update Task.job
  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-1645522239-1292428093-682003330-1003
  • %Program Files%\Browsersafeguard\TrustedRoot.cer

Step 7

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.
  • %Program Files%\Browsersafeguard
  • %Program Files%\Browsersafeguard\Resources
  • %Start Menu%\Programs\BrowserSafeguard

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as ADW_BGUARD. 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 9

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.

    • %Application Data%\GDIPFONTCACHEV1.DAT
    • %User Profile%\Application Data\Microsoft

Step 10

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.

  • %Windows%\Tasks\Temp{1cba5f87-9fd8-4fe4-b0f1-3ee0156e3ef4}.job
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\security.config.cch.428.181843
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\config\enterprisesec.config.cch.428.181843
  • %User Profile%\v2.0.50727.42\security.config.cch.428.181984


Did this description help? Tell us how we did.