Trojan.Win32.DOWNLOADER.BB
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan 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 Trojan 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 Trojan drops the following files:
- {Malware File Path}\config.ini
Other System Modifications
This Trojan adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
(Default) = (value not set)
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
DisplayIcon = {Malware File Path}
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
DisplayVersion =
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
DisplayName = {Foreign Character}
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
InstallLocation = {Malware File Path}\MaiGuangOffice.exe
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
Publisher = {Foreign Character}
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
UninstallString = {Malware File Path}\uninst.exe
Other Details
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\
Windows\CurrentVersion\Uninstall\
MaiGuangOffice
It connects to the following possibly malicious URL:
- https://{BLOCKED}rtech.com/maiguang?pid=&mid2=6ecec65154d63f22ccc519f7fe9fb70571f934132947&appver=&modver=1.0.0.1025&type=maiguangspeed&action=run&app=
SOLUTION
Step 1
Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.
Step 2
Search and delete this file
- {Malware File Path}\config.ini
Step 3
Delete this registry value
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.
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- (Default) = (value not set)
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- DisplayIcon = {Malware File Path}
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- DisplayName = {Foreign Character}
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- DisplayVersion = {null}
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- InstallLocation = {Malware File Path}\MaiGuangOffice.exe
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- Publisher = {Foreign Character}
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
- UninstallString = {Malware File Path}\uninst.exe
Step 4
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.
- HKEY_LOCAL_MACHINE\SOFTWARE\MIcrosoft\Windows\CurrentVersion\Uninstall\MaiGuangOffice
Step 5
Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.DOWNLOADER.BB. 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 the following Trend Micro Support pages for more information:
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