Threat behavior
Win32/Hybris includes both a virus and worm component. The virus component infects WSOCK32.DLL, enabling the virus to activate when an Internet connection is established. The worm component spreads by monitoring outgoing e-mail traffic and, when a legitimate e-mail is sent, follows that by sending a second email to the same addresses. That email contains a copy of the worm. Win32/Hybris can download plug-ins via anonymous binary postings made to a particular newsgroup, thus the specific actions taken may vary.
The email composed by Win32/Hybris varies depending on the plug-in. Many of the Win32/Hybris email display a blank From address, a blank subject line, and a blank message body. One common variation uses the spoofed From address "Hahaha <hahaha@sexyfun.net" and has the following characteristics:
Subject:
Snowhite and the Seven Dwarfs - The REAL story!
Message body:
Today, Snowhite was turning 18. The 7 Dwarfs always where very educated and polite with Snowhite. When they go out work at mornign, they promissed a
*huge* surprise. Snowhite was anxious. Suddlently, the door open, and the Seven Dwarfs enter...
Attachment names:
Actual filenames may vary depending on the plug-in. Common attachment names include the following:
enano.exe, enano porno.exe, blanca de nieve.scr, enanito fisgon.exe, sexy virgin.scr, joke.exe, midgets.scr, dwarf4you.exe, blancheneige.exe, sexynain.scr, blanche.scr, nains.exe, branca de neve.scr, atchim.exe, dunga.scr, anão pornô.scr.
Prevention
Take the following steps to help prevent infection on your system:
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Enable a firewall on your computer.
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Get the latest computer updates.
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Use up-to-date antivirus software.
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Use caution with attachments and file transfers.
Enable a firewall on your computer
Use a third-party firewall product or turn on the Microsoft Windows XP Internet Connection Firewall.
To turn on the Internet Connection Firewall in Windows XP
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Click Start, and click Control Panel.
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Click Network and Internet Connections. If you do not see Network and Internet Connections, click Switch to Category View.
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Click Change Windows Firewall Settings.
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Select On.
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Click OK.
Get the latest computer updates
Updates help protect your computer from viruses, worms, and other threats as they are discovered. You can use the Automatic Updates feature in Windows XP to automatically download future Microsoft security updates while your computer is on and connected to the Internet.
To turn on Automatic Updates in Windows XP
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Click Start, and click Control Panel.
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Click System.
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Click Automatic Updates.
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Select a setting. Microsoft recommends selecting Automatic. If you do not choose Automatic, but you choose to be notified when updates are ready, a notification balloon appears when new downloads are available to install. Click the notification balloon to review and install the updates.
Use up-to-date antivirus software
Most antivirus software can detect and prevent infection by known malicious software. To help protect you from infection, you should always run antivirus software that is updated with the latest signature files. Antivirus software is available from several sources. For more information, see http://www.microsoft.com/athome/security/downloads/default.mspx
Use caution with attachments and file transfers
Exercise caution with e-mail and attachments received from unknown sources, or received unexpectedly from known sources. Use extreme caution when accepting file transfers from known or unknown sources.
