linux - HACKINGISCOOL

HACKINGISCOOL

linux

A collection of 7 posts

Stack-canary (ROP), format string leak plus how I learned that nullbyte is not a badchar to scanf("%s",buf) - while socat ignores read on STDIN - MBE LAB8A

This time we are having some fun with a standard null-armored stack canary, as well as an additional custom one (we will extensively cover both scenarios, as there's plenty of subject matter here), plus some peculiarities regarding scanf() and read(). The relevant MBE lecture can be found here

Out-of-bound read-write without integer sign flipping - MBE LAB8B walkthrough - the bonus version without using thisIsASecret() function

Introduction This is the continuation of https://hackingiscool.pl/out-of-bounds-write-with-some-integer-sign-flipping-mbe-lab8b-walkthrough-the-basic-version/ - the bonus version not utilizing the thisIsASecret() function to get the shell. So, the basic version was in fact very simple after figuring out how to control EIP. We just overwrote it with a pointer to this function: Now,

Out-of-bounds read-write with some integer sign flipping - MBE LAB8B walkthrough - the basic version

I decided to skip the LAB8C (https://github.com/RPISEC/MBE/blob/master/src/lab08/lab8C.c) writeup, as solving it did not even require running gdb - so I was like "muh". Instead, let's look at LAB8B. The target app As usual, here's

Heap overflow with stack-pivoting, format string mem leaking and first-stage ROP-ing to shellcode after making it executable on the heap - on a statically linked binary (MBE LAB7A)

This is was one of the most painstaking ones (which is reflected in the length of this write up). While finding the vulnerability was trivial, building a working exploit was quite of a challenge here. The target app The target app https://github.com/RPISEC/MBE/blob/master/src/lab07/

Exploiting the same Use after Free twice to leak the mem layout and execute code - MBE LAB7C walkthrough

The target app This time we are dealing with a very plain and simple UaF vulnerability. The source code can be found here: https://github.com/RPISEC/MBE/blob/master/src/lab07/lab7C.c Right away we can see two data structure definitions, which more-less suggest what we are going

The XOR madness of MBE's tricky lab6B - a walkthrough

This post is a continuation of my MBE (Modern Binary Exploitation) walkthrough series. In order to get some introduction, please see the previous post: https://hackingiscool.pl/mbe-lab6c-walkthrough/. A look at the target app So let's get right to it. The source code of the target application can

MBE lab6C walkthrough

About MBE Some time ago I came across RPISEC's free Modern Binary Exploitation course (https://github.com/RPISEC/MBE) which I can't recommend enough. You get lectures, challenges and a ready out-of-the-box operational Ubuntu VM to play with. Yup, this course is Linux-focused, which made it

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