F-Secure researchers have recently spotted a new Zeus 2.x variant that includes a ransomware feature.
Once this particular piece of malware is executed, it first opens Internet Explorer and points it towards a specific URL (lex.creativesandboxs.com/locker/lock.php). Simultaneously, the users are blocked from doing anything on their computer.
The site in question is offline, so it is difficult to say for sure what it contained, but a good guess would be an extortion message.
The command for "unlocking" the computer is present on the computer, in the registry, so it is possible to do so without paying the ransom.
According to the researchers, users who have found themselves effectively locked out of the computer must do the following:
1. boot the system in safe mode
2. add a new key named syscheck under HKEY_CURRENT_USER
3. create a new DWORD value under the syscheck key
4. set the name of the new DWORD value to Checked
5. set the data for the Checked value to 1
Obviously, the threat of having their financial and login information stolen after having unlocked the computer is still present, as the aforementioned steps haven't rid them of the malware.