Modified by: Rika Joi Gregorio
ALIASES:

a variant of Win32/Toolbar.Montiera.H application (Symantec), a variant of Win32/Toolbar.Escort.A application(Eset), Montiera (fs)(Sunbelt)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Adware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This adware may arrive bundled with malware packages as a malware component. It may be manually installed by a user.

  TECHNICAL DETAILS

File Size: 380,928 bytes
File Type: EXE
Initial Samples Received Date: 23 Feb 2014
Payload: Connects to URLs/IPs

Arrival Details

This adware may arrive bundled with malware packages as a malware component.

It may be manually installed by a user.

Installation

This adware drops the following files:

  • {Malware Path}\app.ini

Autostart Technique

This adware registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}

It registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}
(Default) = "buenosearch Helper Object"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}
NoExplorer = "1"

Other System Modifications

This adware adds the following registry keys:

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr\CLSID

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr\CurVer

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr.1

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr.1\CLSID

HKEY_CLASSES_ROOT\AppID\escort.DLL

HKEY_CLASSES_ROOT\AppID\{09C554C3-109B-483C-A06B-F14172F1A947}

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
Implemented Categories

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
Implemented Categories\{59FB2056-D625-48D0-A944-1A85B5AB2640}

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
InprocServer32

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
ProgID

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
Programmable

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
TypeLib

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
VersionIndependentProgID

It adds the following registry entries:

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr
(Default) = "CescrtHlpr Object"

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr\CLSID
(Default) = "{F1C81E40-2485-4DB6-8C9D-04BD596B281E}"

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr\CurVer
(Default) = "buenosearch.buenosearchHlpr.1"

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr.1
(Default) = "CescrtHlpr Object"

HKEY_CLASSES_ROOT\buenosearch.buenosearchHlpr.1\CLSID
(Default) = "{F1C81E40-2485-4DB6-8C9D-04BD596B281E}"

HKEY_CLASSES_ROOT\AppID\escort.DLL
AppID = "{09C554C3-109B-483C-A06B-F14172F1A947}"

HKEY_CLASSES_ROOT\AppID\{09C554C3-109B-483C-A06B-F14172F1A947}
(Default) = "escort"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}
(Default) = "buenosearch Helper Object"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}
AppID = "{09C554C3-109B-483C-A06B-F14172F1A947}"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
InprocServer32
(Default) = "{adware path and file name}"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
InprocServer32
ThreadingModel = "apartment"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
ProgID
(Default) = "buenosearch.buenosearchHlpr.1"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
TypeLib
(Default) = "{09C554C3-109B-483C-A06B-F14172F1A947}"

HKEY_CLASSES_ROOT\CLSID\{F1C81E40-2485-4DB6-8C9D-04BD596B281E}\
VersionIndependentProgID
(Default) = "buenosearch.buenosearchHlpr"

Other Details

This adware connects to the following possibly malicious URL:

  • {BLOCKED}g.{BLOCKED}rservices.com
  • {BLOCKED}s.{BLOCKED}ra.com

NOTES:

All information related to registry creation are found in the file buenosearchTlbr.dll.

  SOLUTION

Minimum Scan Engine: 9.700
SSAPI PATTERN File: 1.487.00
SSAPI PATTERN Date: 26 Feb 2014

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_CLASSES_ROOT
    • buenosearch.buenosearchHlpr
  • In HKEY_CLASSES_ROOT
    • buenosearch.buenosearchHlpr.1
  • In HKEY_CLASSES_ROOT\AppID
    • escort.DLL
  • In HKEY_CLASSES_ROOT\AppID
    • {09C554C3-109B-483C-A06B-F14172F1A947}
  • In HKEY_CLASSES_ROOT\CLSID
    • {F1C81E40-2485-4DB6-8C9D-04BD596B281E}
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects
    • {F1C81E40-2485-4DB6-8C9D-04BD596B281E}

Step 3

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


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