Zar.A

Classification

Malware

Virus

W32

W32/Zar.A@mm, Email-Worm.Win32.Zar.A

Summary

Zar.A is a simple massmailer that attempts to spread on emails with subject "Tsunami Donation! Please help!".

Automatic action

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.

Suspect a file is incorrectly detected (a False Positive)?

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:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest detection database updates, then try scanning the file again.

  • 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.

  • 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.

For more Support

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User Guide

See the user guide for your product on the Help Center.

Contact Support

Chat with or call an expert for help.

Submit a sample

Submit a file or URL for further analysis.

Technical Details

When run, Zar.A makes three copies of itself with the following names:

  • %WinDir%\raz32.exe
  • %WinDir%\crssr.exe
  • %WinDir%\tsunami.exe

where %WinDir% is Windows folder, for example 'C:\Windows\' on a default installation of Windows XP. The "crssr.exe" file is added to the registry key

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
 "CaptionMgr32" = "%systemroot%\crssr.exe"

As %systemroot% usually refers to same directory as %Windir%, this registry key ensures that the worm is run at every system startup.

Email spreading

Zar.A tries to find addresses from Microsoft Outlook address book. It uses the MAPI functions for sending infected messages for each of the addresses found in the address book.

The message is composed of subject

"Tsunami Donation! Please help!"

and message body text

"Please help us with your donation and view the attachment below! We need you!"

The worm attaches itself in messages using filename "tsunami.exe".

Payload

Zar.A attempts a Denial Of Serice attack against www.hacksector.de by issuing ICMP echo messages (ping) with huge payload.

It can also display a fake error message saying

"Fatal Error: Couldn't initialize setup (CRC)"