The Simatic WinCC SCADA system, which runs on Windows and is used by many utilities and factories, uses a database that is protected by a hard-coded password that has been publicly revealed on a couple of forums back in 2008.
The worm takes advantage of a yet unpatched Windows vulnerability affecting the way that Windows handles shortcut files, which allows it to spread via CDs, USB sticks or file-sharing among computers in a network.
If it finds SCADA software, the worm proceeds to enter the database and search project files, then tries to copy them to an external website. If it fails to find said software, it simply copies itself somewhere on the system and lays dormant.
This particular worm is obviously intent on stealing all the information about the way that these companies work - counterfeiters will have a field day with it.
The worm is spreading like fire - Symantec registers some 9,000 attempts of infection per day. SCADA users are panicking and consider changing the hard-coded password.
Siemens recommends against it, as it could disrupt the whole system. According to Network World, they promise to publish a customer guidance document soon, but they say that the solution will definitely now involve a change of password. They also mean to set up a website that will offer details about the worm.
In the meantime, Microsoft has released a security advisory regarding the vulnerability, and advises users to disable icons from being displayed for shortcuts and/or disable the WebClient service.
Siemens' spokesman Michael Krampe said that the company "has started to develop a solution, which can identify and systematically remove the malware," but didn't offer a date for the release of the software.
Reading our newsletter every Monday will keep you up-to-date with security news.
Receive a daily digest of the latest security news.