Malware
Malware authors target bugs, or loopholes, to exploit. A common method is exploitation of a buffer overrun vulnerability, where software designed to store data in a specified region of memory does not prevent more data than the buffer can accommodate being supplied. Malware may provide data that overflows the buffer, with malicious executable code or data after the end; when this payload is accessed it does what the attacker, not the legitimate software, determines.
MalwareMustDie
MalwareMustDie is also known for their efforts in original analysis for a new emerged malware or botnet, sharing of their found malware source code to the law enforcement and security industry, operations to dismantle several malicious infrastructure, technical analysis on specific malware's infection methods and reports for the cyber crime emerged toolkits.