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Backdoor.OptixPro.13
Backdoor.OptixPro.13 is a Trojan horse that gives a remote attacker full remote access to your computer. By default, the Trojan opens port 3410 for listening.
Also Known As: Backdoor.Optix.Pro.13 [KAV]
Variants: Backdoor.OptixPro.12, Backdoor.OptixPro.12.b, Backdoor.OptixPro.11, Backdoor.OptixPro.11.b, Backdoor.OptixPro.10, Backdoor.OptixPro.10.b, Backdoor.OptixPro.10.c
Type: Trojan Horse
Infection Length: varies, multiple files
Systems Affected: Windows 95, Windows 98, Windows NT, Windows 2000, Windows XP, Windows Me
Systems Not Affected: Windows 3.x, Macintosh, OS/2, UNIX, Linux
Damage - Payload:
- Compromises security settings: Allows unauthorized remote access to an infected computer
Distribution
[img]http://securityresponse.symantec.com/avcenter/graphics/ssrc/writeups/section_title_technical.gif[/img]
Backdoor.OptixPro.13 is a new version of Backdoor.OptixPro.12.b, which a readily available Backdoor Trojan tool generates.
Files
Backdoor.OptixPro.13 copies itself to either the %Windir% or %System% folder as <name of original Trojan file> and <name of shell hook file>. This action varies and depends on the configuration settings in the Trojan.
NOTES:
- %Windir% is a variable: The Trojan locates the Windows installation folder (by default, this is C:\Windows or C:\Winnt) and copies itself to that location
- %System% is a variable: The Trojan locates the System folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).
- <name of original Trojan file> represents the filename of the Trojan, as chosen by the hacker.
- <name of shell hook file> represents the filename of the Trojan when handling the execution of the .exe files. The hacker also chooses this
Registry changes
Backdoor.OptixPro.13 creates a string value under the registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
RunServices
so that Backdoor.OptixPro.13 is executed each time you start Windows.
This registry value is of the form:
"<registry value name>"="<path to trojan file>"
The hacker chooses the <registry value name>.
Registry shell hook
Backdoor.OptixPro.13 hooks the execution of the executable files, by changing the (Default) value of the registry key:
HKEY_CLASSES_ROOT\exefile\shell\open\command
to:
<path to shell hook file as>
System files
Backdoor.OptixPro.13 modifies the Run= line of the Win.ini file to:
Run=<path to trojan file>
as well as the Shell= line of the System.ini file to:
Shell=Explorer.exe <path to trojan file>
Ports
Backdoor.OptixPro.13 opens a listening port on port 3410. (This is the default port, but the attacker can configure the Backdoor Trojan to any other port.)
Functionality
Backdoor.OptixPro.13 allows a hacker to do the following:
Power options
- Log off the current user
- Reboot the system
- Shut down the system
- Suspend the system
- Crash the system, causing a blue screen to appear
Backdoor information
Obtain information about the running Trojan
File system
- Upload and download files
- Execute files
- Create folders
- Delete files and folders
- Rename files and folders
Processes
- List running processes
- Stop running process
Windows tasks
- Minimize windows
- Maximize windows
- Change the title of windows
- Close windows
- Send keystrokes to specific windows
Registry
- Create new values and keys
- Edit values
- Delete values and keys
FTP server
Launch an FTP server on a specified port
IP scanner
Launch a <IP range>:port scan from the compromised system for the open ports
Port redirection
Redirect connections to the compromised system on a specific port to another computer and port
System information
- Acquire system information, such as the owner, OS version, and key and CPU type and speed
- Steal cached passwords
- Steal AIM passwords
- Steal RAS passwords
System monitoring
- Provide a live feed of the system screen
- Provide a live feed through the system Webcam
- Launch a keylogger
Other
- Open and close the CD-ROM drive
- Show and hide the clock
- Turn the monitor on and off
- Start and stop the screensaver
- Enable and disable the mouse and keyboard
- Produce beeping sounds from the computer's speaker
[img]http://securityresponse.symantec.com/avcenter/graphics/ssrc/writeups/section_title_recommend.gif[/img]
Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":
- Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
- If a blended threat exploits one or more network services, disable, or block access to, those services until a patch is applied
- Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
- Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
- Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files
- Isolate infected computers quickly to prevent further compromising your organization. Perform a forensic analysis and restore the computers using trusted media
- Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
[img]http://securityresponse.symantec.com/avcenter/graphics/ssrc/writeups/section_title_removal.gif[/img]
The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
NOTES:
- If the Trojan has not yet run—that is, the Trojan's file was copied to your computer but has not run—you should be able to follow the instructions in sections 1 and 2, which discuss detecting and removing this file.
- If the worm has run, or if you are unsure of this, first follow the instructions in section 3 (and section 4 if you are running Windows 95/98/Me). After you complete those instructions, follow the steps in sections 1 and 2.
- Update the virus definitions
- Run a full system scan and delete all the files detected as Backdoor.OptixPro.13
- Reverse the changes made to the registry
- Reverse the changes made to the Win.ini and System.ini files.
For specific details on each of these steps, read the following instructions
1. Updating the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
- Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
- Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).
The Intelligent Updater virus definitions are available here. For detailed instructions on how to download and install the Intelligent Updater virus definitions from the Symantec Security Response Web site, click here.
2. Scanning for and deleting the infected files
- Start your Symantec antivirus program and make sure that it is configured to scan all the files
- For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files."
- For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan All Files."
- Run a full system scan
- If any files are detected as infected with Backdoor.OptixPro.13, click Delete
3. Reversing the changes made to the registry
Because the worm modified the registry so that it runs when you start any .exe files, restart the computer in Safe mode or end the Trojans process, make a copy of the Registry Editor as a file with the .com extension, and then run that particular file.
- Do one of the following, depending on the version of Windows you are running
- Windows 95/98/Me/2000/XP users: Restart the computer in Safe mode. All the Windows 32-bit operating systems, except Windows NT 4.0, can be restarted in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode."
- Windows NT 4.0 users: End the Trojan process. To find the name of the process, go back to sections 1 and 2 and write down the names of any files detected as infected with Backdoor.OptixPro.13
- Do one of the following, depending on the version of Windows you are running:
- Windows 95/98 users
- Click Start
- Point to Programs
- Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step c of this section
- Windows Me users
- Click Start
- Point to Programs
- Point to Accessories
- Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step c of this section
- Windows NT 4.0/2000 users
- Click Start, and then click Run
- Type command, and then press Enter. (A DOS window opens.)
- Type cd \winnt, and then press Enter
- Go to step c of this section
- Windows XP users
- Click Start, and then click Run
- Type command, and then press Enter. (A DOS window opens.)
- Type the following:
cd\
cd \windows
Press Enter after typing each one.
- Proceed to step c of this section
- Type copy regedit.exe regedit.com
and then press Enter
- Type start regedit.com
and then press Enter. (The Registry Editor opens in front of the DOS window.)
After you finish editing the registry, exit the Registry Editor, and then exit the DOS window as well.
- Before continuing, Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. For instructions, read the document, "How to make a backup of the Windows registry."
- Navigate to and select the key:
HKEY_CLASSES_ROOT\exefile\shell\open\command
NOTE: The HKEY_CLASSES_ROOT key contains many subkey entries that refer to other file extensions. One of these file extensions is .exe. Changing this extension can prevent any files ending with a .exe extension from running. Make sure that you completely browse through this path until you reach the \command subkey.
Modify the HKEY_CLASSES_ROOT\exefile\shell\open\command subkey, shown in the following figure:
[img]http://securityresponse.symantec.com/avcenter/graphics/backdoor.optixpro.13.1.gif[/img] <<=== NOTE: Modify this key
- In the right pane, double-click the (Default) value.
- Delete the current value data, and then type:
"%1" %*
That is, type the characters: quote-percent-one-quote-space-percent-asterisk.
NOTES
- Under Windows 95/98/Me/NT, the Registry Editor automatically encloses the value within quotation marks. When you click OK, the (Default) value should look exactly like this:
""%1" %*"
- Under Windows 2000/XP, the additional quotation marks will not appear. When you click OK, the (Default) value should look exactly like this:
"%1" %*
- Make sure that you completely delete all the value data in the command key before typing the correct data. If you leave a space at the beginning of the entry, any attempt to run the program files will result in the error message, "Windows cannot find .exe." If this occurs, restart the entire process from the beginning of this section and make sure that you completely remove the current value data.
- Navigate to the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- In the right pane, delete the value:
InternalSystray %system%\<name of original Trojan file>
- Navigate to the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- In the right pane, delete the value:
InternalSystray %system%\<name of original Trojan file>
- Navigate to the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
RunServices
NOTE: This key is not found on all the computers
- In the right pane, delete the value:
InternalSystray %system%\<name of original Trojan file>
- Exit the Registry Editor.
- Do one of the following
- If you are running Windows NT 4.0/2000/XP, restart the computer in Normal mode, and then follow the instructions in sections 1 and 2.
- If you are running Windows 95/98/Me, proceed to section 4.
4. Reversing the changes made to the Win.ini and System.ini files
If you are running Windows 95/98/Me, follow these steps:
- The function you perform depends on your operating system:
- Windows 95/98: Go to step b
- Windows Me: If you are running Windows Me, the Windows Me file-protection process may have made backup copies of the System.ini and Win.ini files, which you need to edit. If these backup copies exist, they will be in the C:\Windows\Recent folder. Symantec recommends that you delete the files before continuing with the steps in this section. To do this:
- Start Windows Explorer
- Browse to and select the C:\Windows\Recent folder
- In the right pane, select the System.ini and Win.ini files and delete them. Windows will regenerate the files.
- Click Start, and then click Run
- Type the following:
edit c:\windows\win.ini
and then click OK. (The MS-DOS Editor opens.)
NOTE: If Windows is installed in a different location, make the appropriate path substitution
- In the [windows] section of the file, look for a line similar to:
Run=%System%\<name of original Trojan file>
- If this line exists, delete the entire line.
- Click File, and then click Save
- Click File, and then click Exit.
- Click Start, and then click Run.
- Type the following:
edit c:\windows\system.ini
and then click OK. (The MS-DOS Editor opens.)
NOTE: If Windows is installed in a different location, make the appropriate path substitution.
- In the [boot] section of the file, look for a line similar to:
shell=Explorer.exe <name of Trojan file>
- If this line exists, delete everything to the right of Explorer.exe.
When you are done, it should look like:
shell=Explorer.exe
- Click File, and then click Save
- Click File, and then click Exit.
- Restart the computer in Normal mode, and then follow the instructions in sections 1 and 2.
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