Buffer Overflow

How Attackers Use It

Attack Summary

Writing more data into a buffer than it can hold overwrites adjacent memory — including the saved return address. Classic technique for redirecting execution to attacker-controlled shellcode.

• Attacker finds an input path with inadequate bounds checking.
• Crafted payload overwrites stack or heap structures.
• Control flow is redirected to shellcode or ROP chains.
• Privilege abuse and persistence follow successful code execution.

Defensive Strategy

Defense Summary

Stack canaries (GCC -fstack-protector). ASLR (address space layout randomisation). NX/DEP (non-executable stack). Use of memory-safe languages (Rust, Go) where possible.

• Adopt memory-safe languages for new security-critical components.
• Enable compiler/runtime protections such as ASLR, DEP, and stack canaries.
• Use fuzz testing and sanitizers in CI for native modules.
• Perform secure code review focused on memory operations.

Detection Signals

• Crashes with segmentation faults under malformed input.
• Exploit-like payload patterns in application logs.
• Unexpected process behavior after memory allocation anomalies.

Internal Resources

• Repositories
• How-To Guides
• General Knowledge