OSX-SHLAYEROSX/Shlayer

The initial Trojan horse infection (the fake Flash Player installer) component of OSX/Shlayer leverages shell scripts to download additional malware or adware onto the infected system. The primary goal of OSX/Shlayer is to download and install adware onto an infected Mac. Although "adware" may not sound like a big deal, it can be a lot more harmful than the name implies; be sure to watch our aforementioned interview with Amit Serper to learn more about one particular example of malicious Mac adware. At least one variant of the malware also appears to exhibit an interesting behavior: It checks whether one of several Mac anti-virus products is installed.