Win32/Koobface is a multi-component family of malware used to compromise machines and direct them in various ways at the attacker's will. This could include using the affected machine to distribute additional malware, generate 'pay per click' advertising revenue, steal sensitive data, break captchas, and subvert the affected user's online experience. Its components are varied, but include a worm that spreads by utilizing social networking sites such as Facebook and MySpace.
If this worm is executed, Win32/Koobface copies itself to the Windows folder as in the following examples:
The worm may drop a cleanup Batch script file also having a random file name to the root of the local drive, as in this example:
The worm may execute the cleanup batch script to remove the originally executed worm and to remove itself. The registry is modified to execute the dropped worm copy at each Windows start.
Adds value: systray
With data: "%windir%/<worm file name>"
To subkey: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Depending on the variant, other values are created instead such as "sysftray2" or "sysldtray".
MySpace and FaceBook Contacts
Win32/Koobface searches in the default Internet Explorer cookies folder for browser cookies related to the Internet social network sites including the following:
In some variants of Win32/Koobface, if the worm determines that none of these sites are visited, the worm may delete itself and may display following message box:
In the wild, the worm may connect to the Web site 'zzzping.com' to download and execute malware.
The worm spreads by sending messages containing a hyperlink to a copy of worm to friends or contacts of the infected user. Friends that receive the message may visit the link to download the worm and repeat the cycle of spreading to others.
Removes Audible Navigation Alerts
Some variants of Win32/Koobface may delete a registry subkey that references navigation sounds such as the 'click' sound when navigating from one Web site to another. The following subkey may be deleted by the worm:
Analysis by Vitaly Zaytsev
The following system changes may indicate the presence of this malware:
Take the following steps to help prevent infection on your computer:
Enable a firewall on your computer.
Get the latest computer updates for all your installed software.
Use up-to-date antivirus software.
Limit user privileges on the computer.
Use caution when opening attachments and accepting file transfers.
Use caution when clicking on links to Web pages.
Avoid downloading pirated software.
Protect yourself against social engineering attacks.
Use strong passwords.
Enable a firewall on your computer
Use a third-party firewall product or turn on the Microsoft Windows Internet Connection Firewall.
Get the latest computer updates
Updates help protect your computer from viruses, worms, and other threats as they are discovered. It is important to install updates for all the software that is installed in your computer. These are usually available from vendor Web sites.
You can use the Automatic Updates feature in Windows to automatically download future Microsoft security updates while your computer is on and connected to the Internet.
Use up-to-date antivirus software
Limit user privileges on the computer
Starting with Windows Vista and Windows 7, Microsoft introduced User Account Control (UAC), which, when enabled, allowed users to run with least user privileges. This scenario limits the possibility of attacks by malware and other threats that require administrative privileges to run.
You can configure UAC in your computer to meet your preferences:
Use caution when opening attachments and accepting 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.
Use caution when clicking on links to Web pages
Exercise caution with links to Web pages that you receive from unknown sources, especially if the links are to a Web page that you are not familiar with, unsure of the destination of, or suspicious of. Malicious software may be installed in your computer simply by visiting a Web page with harmful content.
Avoid downloading pirated software
Threats may also be bundled with software and files that are available for download on various torrent sites. Downloading "cracked" or "pirated" software from these sites carries not only the risk of being infected with malware, but is also illegal. For more information, see 'The risks of obtaining and using pirated software
Protect yourself from social engineering attacks
While attackers may attempt to exploit vulnerabilities in hardware or software to compromise a computer, they also attempt to exploit vulnerabilities in human behavior to do the same. When an attacker attempts to take advantage of human behavior to persuade the affected user to perform an action of the attacker's choice, it is known as 'social engineering'. Essentially, social engineering is an attack against the human interface of the targeted computer. For more information, see 'What is social engineering?
Use strong passwords
Attackers may try to gain access to your Windows account by guessing your password. It is therefore important that you use a strong password – one that cannot be easily guessed by an attacker. A strong password is one that has at least 8 characters, and combines letters, numbers, and symbols. For more information, see http://www.microsoft.com/protect/yourself/password/create.mspx