A security analyst is auditing a C-based backend service responsible for processing batch user updates. Code analysis reveals that the buffer allocation calculation `total_bytes = user_count * sizeof(user_record_t)` uses an unsigned 32-bit integer. When a caller supplies a very large `user_count`, the multiplication arithmetic wraps around, resulting in a small memory allocation from `malloc()`. The application then attempts to copy all incoming user records into this undersized buffer, causing arbitrary memory corruption. Which of the following software vulnerabilities is demonstrated in this scenario?
- Integer overflow resulting in a heap-based buffer overflowCevap
- BCross-site scripting (XSS) resulting in DOM-based script injection
- CBroken object level authorization resulting in privilege escalation
- DImplementation of web application firewalls to block malformed packet headers
Cevap
Integer overflow resulting in a heap-based buffer overflow
The scenario describes an arithmetic integer overflow where a calculated memory allocation size exceeds the maximum integer capacity and wraps around to a small value. Passing this reduced value to memory allocation functions causes insufficient memory to be reserved. When the program subsequently writes the entire payload into this undersized allocation, it overwrites adjacent heap memory, leading to a heap-based buffer overflow.
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Anahtar Kavram
Integer Overflow and Buffer Overflow Vulnerabilities