Malicious Software Encyclopedia: Win32/Optix
Published:
August 2, 2005
Win32/Optix is a family of highly configurable backdoor Trojans that targets several versions of Microsoft Windows. The Trojan opens a backdoor that allows an attacker to control an infected computer remotely. It can also release system information to an attacker and disable security-related and other programs.
On This Page
Threat Overview
| Class/type | Trojan - Backdoor
|
| Discovered | December 11, 2001 |
| Circulating | Yes |
| Affected operating systems | Windows NT 4.0
Windows 95
Windows 2000
Windows XP
Windows Server 2003
|
| Affected software |
Not specified
|
| Infection rating | Medium |
| Recovery difficulty | Difficult |
| Damage rating | Medium |
| Transmission rating | Medium |
Aliases (Also Known As)
Different antivirus vendors may be using different names to refer to this malicious software. Here are some of the names currently in use by antivirus software vendors participating in the Microsoft Virus Information Alliance (VIA):
CA:
Backdoor/OptixSymantec:
Backdoor.Optix
Learn more about the
Microsoft Virus Information Alliance.
Technical Analysis
When Win32/Optix runs, it can take the following actions:
- Modify the Windows registry so that the Trojan runs each time Windows starts.
- Create a copy of itself in a location that the Trojan specifies in a registry key.
- Disable security-related and other programs.
- Display false error messages.
- Run programs that it downloads from a Web site.
- Send infection notifications to an attacker using an instant messaging program or a Web page.
Win32/Optix can open a backdoor that can be used to:
- Terminate processes.
- Run programs remotely.
- Download programs from a Web site.
- Release system information to an attacker.
How to Prevent Infection
Take the following steps to help prevent infection on your system:
Enable a firewall on your computer.
Get the latest computer updates.
Use up-to-date antivirus software.
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
Click Start, and click Control Panel.
Click Network and Internet Connections, and click Network Connections. If you do not see Network and Internet Connections, click Switch to Category View.
Highlight a connection that you want to help protect, and click Change settings of this connection.
Click Advanced, and select Protect my computer and network by limiting or preventing access to this computer from the Internet.
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 Microsoft 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
Click Start, and click Control Panel.
Click Performance and Maintenance. If you do not see Performance and Maintenance, click Switch to Category View.
Click System.
Click Automatic Updates, and select Keep my computer up to date.
Select a setting. Microsoft recommends selecting Automatically download the updates, and install them on the schedule that I specify and setting a regular update time.
If you choose to have Automatic Updates notify you in step 5, you will see a notification balloon when new downloads are available to install. Click the notification balloon to review and install updates.
Use up-to-date antivirus software
Most antivirus software can detect and prevent infection by known malicious software. You should always run antivirus software on your computer that is updated with the latest signature files to automatically help protect you from infection. If you don't have antivirus software installed, you can get it from one of several companies. For more information, see http://www.microsoft.com/athome/security/downloads/default.mspx
How to Tell If Your Computer Is Infected
Win32/Optix infection symptoms vary because attackers can customize the actions of this Trojan.
How to Recover from Infection
Automatic Recovery
To attempt to automatically remove this threat, run one of the following removal tools:
Payload Information
| Payload type | Trigger | Description |
|---|
| Compromises Security | Execution | - Disables security-related applications.
- Opens a backdoor that allows an attacker to control the computer remotely.
|
| Release information | Execution | - Releases system information to an attacker through a backdoor.
- Sends infection notifications to an attacker using instant messaging or a Web page.
|
