BufferOverFlow

In computer security and programming, a buffer overflow, or
buffer overrun, is an anomaly where a program, while
writing data to a buffer, overruns the buffer's boundary and
overwrites adjacent memory. This is a special case of
violation of memory safety.
Buffer overflows can be triggered by inputs that are designed
to execute code, or alter the way the program operates. This
may result in erratic program behavior, including memory
access errors, incorrect results, a crash, or a breach of system
security. They are thus the basis of many software
vulnerabilities and can be maliciously exploited.
Programming languages commonly associated with buffer
overflows include C and C++, which provide no built-in
protection against accessing or overwriting data in any part of
memory and do not automatically check that data written to
an array (the built-in buffer type) is within the boundaries of
that array. Bounds checking can prevent buffer overflows.