Once there, copy and paste each one of the code strings below into the terminal window. In its newer Java-related variants, the software could install itself without the user having to click on anything or provide it with a password. It didn't help that Apple hasn't shipped Flash on its computers for well over a year, arguably creating a pool of users more likely to run the installer in order to view popular Web sites that run on Flash. In its initial incarnation, the malware looked very similar to Adobe's Flash installer. The simple answer is that the software was designed to do exactly that.
More advanced versions would install quietly in the background with no password needed. The malware evolved to target the Java runtime on OS X, where users visiting malicious sites would then be prompted to install it on their machine in order to view Web content. Flashback as we know it now appeared near the end of September last year, pretending to be an installer for Adobe's Flash, a widely used plug-in for streaming video and interactive applications that Apple no longer ships on its computers.