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1. Buffer Overflow 1.1. Security Vulnerabilities 1.1.1. Causes Buffer Overflow is a security vulnerability where data is written beyond the size of a buffer, overwriting adjacent memory. When data is written past the buffer boundary, adjacent memory gets overwritten . 1.1.2. Impact and Risks The program may crash abnormally or produce errors. Critical data may be corrupted, causing unexpected behavior . An attacker may manipulate memory to execute arbitrary code or take control of the system . 1.2. Stack Buffer Overflow Stack Buffer Overflow is a vulnerability in which data is written beyond the size of a buffer allocated in the Stack area, overwriting adjacent memory regions. The main causes are insufficient input length validation and the use of unsafe functions that do not perform bounds checks. # include <stdio.h> # include <string.h> # include <stdlib.h> // Demonstrate stack buffer overflow: // Stac...

1. C Language Pointers A pointer in C is a variable that stores a memory address. It stores the "location" (address) where data resides . #include <stdio.h> #include <string.h> #include <stdlib.h> int main() { const char *pstr = "Hello World!"; char *ptr = NULL ; const size_t len = strlen (pstr); ptr = malloc (len + 1); memset (ptr, 0x00, len + 1); memcpy (ptr, pstr, len); printf ("%p[%p] → %s\n", &ptr, ptr, ptr); free (ptr); return 0; } The ptr pointer variable resides in the Stack region . Using malloc , a memory space is allocated in the Heap region , and its address is stored in the Stack region ptr variable. Via memcpy , the "Hello World!" string data is copied into the allocated space in the Heap region . 0x7ffffc12fd50[0x5a14a05396b0] → Hello World! &ptr is the address of the pointer varia...

1. C Language Strings In the C language, a string can be defined as a continuous memory area of characters (char) terminated by a Null character ('\0') . The Null character is represented as '\0' or 0x00 . There is no dedicated data type for representing strings; string handling is performed through pointers and arrays. #include  <stdio.h> #include  <string.h>      int   main () {      char  str[ 16 ];           strcpy (str,  "012345678901234" );      printf ( "%s,len=%zu,size=%zu\n" , str,  strlen (str),  sizeof (str));           return   0 ; } ※ Local variables declared without initialization, such as  char str[32] , have their memory space filled with undefined values (garbag...

1. RBI Server Implementation Technologies RBI (Remote Browser Isolation) goes beyond simply "running a browser remotely" and is an architecture where  server infrastructure, networking, streaming, and security technologies are combined . It requires a system architecture designed for large-scale scalability and integration with cloud infrastructure, and it must provide stable service across multiple access points. 1.1. Server Technologies 1.1.1. Edge Computing  RBI minimizes network latency by running the browser on edge nodes geographically close to users. In this model, edge servers function not as simple content caches, but as the actual execution location of browser instances. Technology Elements Multi-region edge node deployment and region-based traffic routing Global load balancing based on Geo DNS or Anycast Distribution of service touchpoints through PoP (Point of Presence) configuration 1.1.2. Screen Streaming The browser screen running on...