Fortunately, Bitcoin’s implementation has proven very resilient to attacks thus far, with some exceptions. In August 2010, a bug where the sum of two outputs overflowed to a negative number allowed attackers to create two outputs of 92233720368.54 coins from an input of 0.50 coins. More recently, massive vulnerabilities such as the heartbleed bug have been discovered in the OpenSSL libraries. These vulnerabilities have one thing in common, they happened because languages like C and C++ do not perform any checks on the operations they perform. For the sake of efficiency, they may access random parts of the memory, add integers larger than natively supported, etc. While these vulnerabilities have spared Bitcoin, they do no not bode well for the security of the system.