Which type of denial of service attack exploits the existence of software flaws to disrupt a service?

The denial of service attack that exploits the existence of software flaws to disrupt a service is the teardrop attack. The teardrop attack exploits flaws in the way older operating systems handled fragmented Internet Protocol (IP) packets.
Fragmented packets are sent to a target machine but the target machine  cannot reassemble them due to a bug in TCP/IP fragmentation reassembly, the packets overlap one another. This results in crash in the target network device. 

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