EkoParty - Advanced Fuzzing Workshop

Next editions

All you need for the workshop is:

A running Linux system with an internet connection
Latest version of AFL++ installed on the system (https://github.com/AFLplusplus/AFLplusplus#building-and-installing-afl). You can download AFL++ source code at https://github.com/AFLplusplus/AFLplusplus/releases.

You also can find an .OVF virtual machine with everything already set up for the workshop here

After booting the VM, open a terminal and go to Desktop -> WORKSHOP -> Fuzz 0 -> unrtf

Then, type:

afl-fuzz -i ./tests -o afl-output  -- ./bin/unrtf --verbose -P ./lib/unrtf/ @@

If all it's ok, you'll be able to see a lot of AFL crashes :)

It's a CTF-style hands-on workshop.
There will be 3 different challenges. The goal is to find a reproducible bug on each of them.
We're looking for exploitable vulnerabilities. In order to be the winner of a challenge, you must provide a crash/PoC. "Theoretical bugs" or code warnings are not welcome, sorry.
Challenges are intended to be solved by fuzzing, but creative approaches will be encouraged.
During the workshop you will be able to ask me any questions you might have (via a private message). Please don't share solutions while the challenge is live.
I will give you some hints and tips before and during the challenge.
After each challenge, I will show my solution and I will explain it to you.
There may be more than one correct solution.

The winner of each challenge will receive a coupon to spend in GitHub Shop. Second place will also be awarded.

YOU CAN SEND ME THE CRASHES TO MY TWITTER ACCOUNT @nosoynadiemas

Build:

gcc EkoParty1.c -o EkoParty1 -w -lcrypto -lssl

Run:

./EkoParty1 example.ESIF output.ppm

Build:

gcc EkoParty2.c -o EkoParty2 -w -lz

Run (must be run as root):

./EkoParty2

A modified (and vulnerable) UnRTF version

Build:

./configure
make
make install

Run

./unrtf [path]

You can find some examples in the "tests" folder