TROJ_FRAUDLO.NN
Microsoft: Rogue:Win32/Winwebsec; Kaspersky: Trojan-Downloader.Win32.FraudLoad.ibt; Mcafee: FakeAlert-SecurityTool.bt
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
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.
It deletes itself after execution.
It displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.
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 copies of itself into the affected system:
- %System Root%\Documents and Settings\All Users\Application Data\{random folder name}\{random file name}.exe
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It drops the following non-malicious file:
- %System Root%\Documents and Settings\All Users\Application Data\{random folder name}\{random file name}
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It creates the following folders:
- %System Root%\Documents and Settings\All Users\Application Data\{random folder name}
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
{random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random folder name}\{random file name}.exe"
Other Details
This Trojan deletes itself after execution.
Rogue Antivirus Routine
This Trojan displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.
SOLUTION
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Scan your computer with your Trend Micro product and note files detected as TROJ_FRAUDLO.NN
Step 3
Restart in Safe Mode
Step 4
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.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
- {random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random folder name}\{random file name}.exe"
- {random file name} = "%System Root%\Documents and Settings\All Users\Application Data\{random folder name}\{random file name}.exe"
Step 5
Search and delete this folder
- In %System Root%\Documents and Settings\All Users\Application Data\{random folder name}
Step 6
Search and delete the file detected as TROJ_FRAUDLO.NN
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_FRAUDLO.NN. 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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