Copying data to a buffer that is not large enough to hold that data results in a buffer overflow. Buffer overflows occur frequently when manipulating strings [Seacord 2013b2013]. To prevent such errors, either limit copies through truncation or, preferably, ensure that the destination is of sufficient size to hold the character data to be copied and the null-termination character. This rule is a C++-specific instance of STR31-C. Guarantee that storage for strings has sufficient space for character data and the null terminator.
...
[ISO/IEC 14882-2014] | Subclause 27.7.2.2.3, " |
[Seacord 2013b2013] | Chapter 2, "Strings" |
...