ADW_Istbar
Windows
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.
TECHNICAL DETAILS
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:
- %User Temp%\_ir_sf_temp_0
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Other System Modifications
This adware deletes the following files:
- %User Temp%\_ir_sf_temp_0\irsetup.exe
- %User Temp%\_ir_sf_temp_0\lua5.1.dll
- %User Temp%\IRW8.tmp
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It adds the following registry keys:
HKEY_CURRENT_USER\Software\VitaSFSS
Dropping Routine
This adware drops the following files:
- %User Temp%\_ir_sf_temp_0\irsetup.dat
- %User Temp%\_ir_sf_temp_0\IRIMG1.JPG
- %User Temp%\_ir_sf_temp_0\IRIMG2.JPG
- %User Temp%\_ir_sf_temp_0\dxdiag.enc
- %User Temp%\CodecFixDivx.exe
- %User Temp%\dxdiag.exe
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Other Details
This adware connects to the following possibly malicious URL:
- http://{BLOCKED}oad39.club/?{random characters}
- {BLOCKED}.117.176
- {BLOCKED}.71.56
- {BLOCKED}.141.184
This report is generated via an automated analysis system.
SOLUTION
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
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
- VitaSFSS
Step 3
Search and delete these components
- %User Temp%\_ir_sf_temp_0\irsetup.dat
- %User Temp%\_ir_sf_temp_0\IRIMG1.JPG
- %User Temp%\_ir_sf_temp_0\IRIMG2.JPG
- %User Temp%\_ir_sf_temp_0\dxdiag.enc
- %User Temp%\CodecFixDivx.exe
- %User Temp%\dxdiag.exe
Step 4
Search and delete this folder
- %User Temp%\_ir_sf_temp_0
Step 5
Scan your computer with your Trend Micro product to delete files detected as ADW_Istbar. 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 6
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%\_ir_sf_temp_0\irsetup.exe
- %User Temp%\_ir_sf_temp_0\lua5.1.dll
- %User Temp%\IRW8.tmp
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