Bropia.F
Summary
Bropia.F is a minor variant of Bropia.A. Like the previous variants, it uses MSN messenger for spreading. It also drops a variant of Rbot on the infected system.
Removal
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
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Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
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Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
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Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
Technical Details
When run, the worm copies itself as "msnus.exe" in the Windows system directory. Then it checks files:
winhost.exe winis.exe dnsserv.exe
If these files are not found, it drops file "cz.exe" and executes it. This file is a variant of Rbot. When "cz.exe" is run, it copies itself as "winhost.exe" in the Windows system directory and adds the following registry keys:
[HKLM\Software\Microsoft\Windows\CurrentVersion\Run] "win32" = "%SysDir%\winhost.exe"
This ensures that it will be executed at next system startup. The bot can be used as a backdoor, collecting system information, logging keystrokes, relaying spam and for various other purposes.Brobia.F also drops a file "sexy.jpg" and opens it. On default installation of Windows, the program associated with jpg-extension is usually Internet Explorer. When opened with Internet Explorer, the picture looks like this:
MSN spreading
The worm copies itself in C-directory using one of the following filenames:
LOL.scr Webcam.pif bedroom-thongs.pif naked_drunk.pif LMAO.pif ROFL.pif underware.pif Hot.pif new_webcam.pif
Then it attempts to send this file using MSN messenger to all active MSN contacts. The recipient has to accept and open the file to get infected by the worm.