Freeing memory multiple times has similar consequences to accessing memory after it is freed. The underlying data structures that manage the heap can become corrupted in a way that could introduce security vulnerabilities into a program. In practice, these are referred to as double-free vulnerabilities. To eliminate double-free vulnerabilities, it is necessary to guarantee that dynamic memory is freed only once. Additionally, programmers Programmers should be wary when freeing memory in a loop or conditional statement, if coded incorrectly, these constructs can lead to double-free vulnerabilities.
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