Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an adversary. As a consequence, an adversary is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the adversaries' choice.

An attacker sends a SOAP request with an array whose actual length exceeds the length indicated in the request. When a data structure including a SOAP array is instantiated, the sender transmits the size of the array as an explicit parameter along with the data. If the server processing the transmission naively trusts the specified size, then an attacker can intentionally understate the size of the array, possibly resulting in a buffer overflow if the server attempts to read the entire data set into the memory it allocated for a smaller array. This, in turn, can lead to a server crash or even the execution of arbitrary code.