CMD Simulator

Use-After-Free - Dangling Pointers

Understand use-after-free: accessing memory after it has been freed.

Use-After-Free

Use-after-free occurs when you access memory after calling free() on it.

Why It's Dangerous

  • The memory may be reused by another allocation
  • Reading or writing can corrupt data or crash the program
  • Security vulnerabilities (exploitable by attackers)

How to Avoid

  • Set pointers to NULL after freeing
  • Avoid keeping multiple pointers to the same block
  • Use tools like MemC to visualize and catch these errors