The output from the printf() statement would be: Strlen() output: 0
Wcslen() output: 53
Potential Mitigations
Phase
Description
Always verify the length of the string unit character.
Use length computing functions (e.g. strlen, wcslen, etc.)
appropriately with their equivalent type (e.g.: byte, wchar_t,
etc.)
Other Notes
There are several ways in which improper string length checking may result
in an exploitable condition. All of these, however, involve the introduction
of buffer overflow conditions in order to reach an exploitable state. The
first of these issues takes place when the output of a wide or multi-byte
character string, string-length function is used as a size for the
allocation of memory. While this will result in an output of the number of
characters in the string, note that the characters are most likely not a
single byte, as they are with standard character strings. So, using the size
returned as the size sent to new or malloc and copying the string to this
newly allocated memory will result in a buffer overflow. Another common way
these strings are misused involves the mixing of standard string and wide or
multi-byte string functions on a single string. Invariably, this mismatched
information will result in the creation of a possibly exploitable buffer
overflow condition. Again, if a language subject to these flaws must be
used, the most effective mitigation technique is to pay careful attention to
the code at implementation time and ensure that these flaws do not
occur.