An integer overflow can be triggered in SQLite’s `concat_ws()` function. The resulting, truncated integer is then used to allocate a buffer. When SQLite then writes the resulting string to the buffer, it uses the original, untruncated size and thus a wild Heap Buffer overflow of size ~4GB can be triggered. This can result in arbitrary code execution.
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
| Link | Tags |
|---|---|
| https://sqlite.org/src/info/498e3f1cf57f164f | patch |