Thilan Dissanayaka Exploit development Apr 12, 2026

Exploiting a heap buffer overflow in linux

In the previous article, we dissected glibc's malloc — chunks, bins, tcache, coalescing, and the metadata that holds it all together. Now we break it.

Heap exploitation is fundamentally different from stack exploitation. On the stack, the goal is clear: overwrite the return address, control EIP. On the heap, there's no return address to overwrite. Instead, we corrupt the allocator's metadata to trick malloc() into returning a pointer to memory we want to control — a function pointer, a GOT entry, a vtable, or any other target.

Bypassing DEP with Return-to-libc

DEP makes the stack non-executable — our shellcode can't run. The simplest bypass? Don't inject code at all. Instead, call functions that already exist in libc. In this post, we exploit a stack overflow to call system('/bin/sh') without writing a single byte of shellcode.

Apr 12 Exploit development

Exploiting a Stack Buffer Overflow on Windows

In a previous tutorial we discusses how we can exploit a buffer overflow vulnerability on a Linux machine. I wen through all theories in depth and explained each step. Now today we are going to jump...

Apr 12 Exploit development

Exploiting a heap buffer overflow in linux

In the [previous article](/heap-internals-how-glibc-malloc-works/), we dissected glibc's malloc — chunks, bins, tcache, coalescing, and the metadata that holds it all together. Now we break...

Feb 15 Application Security

Error based SQL Injection

In the previous example, we saw how a classic SQL Injection Login Bypass works. SQL Injection is not all about that. The real fun is we can extract the data from the database. In this tutorial, we...

Mar 01 Cryptography

Basic concepts of Cryptography

Ever notice that little padlock icon in your browser's address bar? That's cryptography working silently in the background, protecting everything you do online. Whether you're sending an email,...

Feb 10 Application Security

SQL Injection Login Bypass

SQL Injection (SQLi) is one of the oldest and most fundamental web application vulnerabilities. While modern frameworks have made it harder to introduce, understanding SQL injection is essential for anyone learning web security. In this post, we'll break it down from the ground up using a classic login bypass.