Denial of Service (DOS)
Denial of service (DoS) is a type of cyber attack designed to disable, shut down or disrupt a network, website or service. Typically, a malware is used to interrupt or inhibit the normal flow of data into and out of a system to render the target useless or inaccessible for a certain period. An example of a DoS attack: when a website is accessed massively and repeatedly from different locations, preventing legitimate visitors from accessing the website.When a DoS attack is launched from different locations in a coordinated fashion, it is often referred to as a distributed denial of service attack (DDoS).
Links : http://blog.trendmicro.com/trendlabs-security-intelligence/android-mediaserver-bug-traps-phones-in-endless-reboots/