Failure to validate the size of a variable before writing it to memory could result in which of the following
application attacks?

A.
Malicious logic

B.
Cross-site scripting

C.
SQL injection

D.
Buffer overflow

Explanation:
A buffer overflow occurs when a program or process tries to store more data in a buffer (temporary data
storage area) than it was intended to hold. Since buffers are created to contain a finite amount of data, the extra
information – which has to go somewhere – can overflow into adjacent buffers, corrupting or overwriting the valid
data held in them. Although it may occur accidentally through programming error, buffer overflow is an
increasingly common type of security attack on data integrity. In buffer overflow attacks, the extra data may
contain codes designed to trigger specific actions, in effect sending new instructions to the attacked computer
that could, for example, damage the user’s files, change data, or disclose confidential information.
Validating the size of a variable before writing it to memory will ensure that the variable can fit into the buffer.
Failure to validate the size of a variable before writing it to memory can result in a buffer overflow.