Microsoft Security Advisory (912920)
Systems that are infected with Win32/Sober.Z@mm may download and run malicious files from certain Web domains beginning on January 6, 2006
Microsoft is aware of the Sober mass mailer worm variant named Win32/Sober.Z@mm. The worm tries to entice users through social engineering efforts into opening an attached file or executable in e-mail. If the recipient opens the file or executable, the worm sends itself to all the contacts that are contained in the system’s address book. Customers who are using the most recent and updated antivirus software are at a reduced risk from infection by the Win32/Sober.Z@mm worm.
On systems that are infected by Win32/Sober.Z@mm, the malware is programmed to download and run malicious files from certain Web domains beginning on January 6, 2006. Beginning approximately every two weeks thereafter, the worm is set to begin downloading and running malicious files from additional sites on the same Web domains.
As with all currently known variants of the Sober worm, the worm does not appear to target a security vulnerability, but rather relies on the user opening an infected attachment.
Microsoft added detection for the latest Sober variants in its December 2005 update to the Malicious Software Removal Tool and in the Windows Live Safety Center.
Customers who believe that they are infected with Sober or are not sure whether they are infected should visit Safety.live.com and choose "Protection Scan" or run the latest version of the Malicious Software Removal Tool from either Microsoft Update or Windows Update to ensure that their systems are free of infection. Additionally, Windows OneCare from Microsoft provides detection for and protection against Sober and its known variants.
Microsoft will release an updated version of the Malicious Software Removal Tool on January 10, 2006, that will further assist in the detection and removal of known malware threats including Sober and its known variants. See Microsoft Knowledge Base Article 891716 for additional details on how to deploy the Malicious Software Removal Tool with the latest definitions to help protect against malware.
For more information about Sober, to help determine whether you have been infected by the worm, and for instructions on how to repair your system if you have been infected, see the Microsoft Virus Encyclopedia. For Microsoft Virus Encyclopedia references, see the “Overview” section. We continue to encourage customers to use caution with unknown file attachments and to follow our Protect Your PC guidance of enabling a firewall, getting software updates, and installing antivirus software. Customers can learn more about these steps by visiting the Protect Your PC Web site.
- Customers must open a malicious e-mail attachment in order to be infected by the worm.
- You can provide feedback by completing the form by visiting the following Web site.
- Customers in the U.S. and Canada can receive technical support from Microsoft Product Support Services. For more information about available support options, see the Microsoft Help and Support Web site.
- International customers can receive support from their local Microsoft subsidiaries. For more information about how to contact Microsoft for international support issues, visit the International Support Web site.
- The Microsoft TechNet Security Web site provides additional information about security in Microsoft products.
The information provided in this advisory is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
- January 03, 2006: Advisory published