void __bin2hex(char *s, const unsigned char *p, size_t len)
{
	int i;
	static const char hex[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

	for (i = 0; i < (int)len; i++) {
		*s++ = hex[p[i] >> 4];
		*s++ = hex[p[i] & 0xF];
	}
	*s++ = '\0';
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.