Mon 02 July 2018 • wallaby • writeup

C64 BASIC Reversing

General problem description You won't find any assembly in this challenge, only C64 BASIC. Once you get the password, the flag is CTF{password}. P.S. The challenge has been tested on the VICE emulator. We got an old .prg file, which is a C64 program file. Parsing the file First we tried using parsers that exist in the wild, that would parse the file for us, but that proved to be not effective, as there were not many and...

Mon 02 July 2018 • wallaby • writeup

JavaScript Anti-Debug

General problem definition You stumbled upon someone's "JS Safe" on the web. It's a simple HTML file that can store secrets in the browser's localStorage. This means that you won't be able to extract any secret from it (the secrets are on the computer of the owner), but it looks like it was hand-crafted to work only with the password of the owner... The assignment was a Javascript file, which needs the Flag as input. Getting to...

Wed 27 June 2018 • cluosh • events

Recap Google CTF Challenges

We've been collaborating with LosFuzzys (https://hack.more.systems) for Google CTF and managed to solve a few challenges. This meetup, we'll go over some of those challenges. Where: @EI3A, TU Wien (Gußhausstraße 25, 1040 Wien, 2nd Floor) When: Thursday, 28.06.2018, 17:30 (CEST) What: Google CTF Recap...

Thu 21 June 2018 • cluosh • events

Wargames

Wargames by the OverTheWire Community (http://overthewire.org/wargames/) are a set of challenges to practice basic security concepts. Where: @EI3A, TU Wien (Gußhausstraße 25, 1040 Wien, 2nd Floor) When: Thursday, 21.06.2018, 17:30 (CEST) What: Wargames...

Wed 13 June 2018 • cluosh • events

Dynamic Analysis with Frida

This meetup we will cover a basic introduction to Frida (https://www.frida.re/), a cross-platform dynamic instrumentation toolkit, and give a practical example of a past CTF challenge. Where: @EI3A, TU Wien (Gußhausstraße 25, 1040 Wien, 2nd Floor) When: Thursday, 14.06.2018, 17:30 (CEST) What: Intro to Frida Practical Example Challenge Frida and Android...

Wed 06 June 2018 • cluosh • events

pwntools/exploit writing

As an introduction to the last internet security challenge, we will give a short overview to writing exploits with pwntools. Where: @EI3A, TU Wien (Gußhausstraße 25, 1040 Wien, 2nd Floor) When: Thursday, 07.06.2018, 17:30 (CEST) What: Intro to pwntools Exploit Writing...

Tue 22 May 2018 • ideal • events

FAUST CTF is coming

Next week, we will participate in FAUST CTF, an online attack-defense CTF. We will meet up at SBA Research and participate together. If you are curious about participating, what CTFs are or what's special about attack-defense CTFs, we are hosting this preparation meetup as part of our weekly CTF/Security meetup series. If you can't make it to the meetup, but still want to participate in the CTF, please contact us. Where: @EI3A, TU Wien (Gußhausstraße 25, 1040...

Thu 17 May 2018 • ideal • events

Intro to reversing: disassembly/side channels

Where: @EI3A, TU Wien (Gußhausstraße 25, 1040 Wien, 2nd Floor) When: Thursday, 17.05.2018, 17:30 (CEST) What: Intro to Reverse Engineering, disassembly and software side channel attacks...

Thu 05 April 2018 • gmerz • events

April Monthly Meetup! As always Open-to-All!

Where: @SBA Research (Favoritenstrasse 16, 1040 Wien, 1st Floor) When: Monday, 09.04.2018, 18:30 (CEST) What: Recap of past CTFs/challenges $YOUR_TOPIC_HERE$ and of course Socializing ;)...

Thu 20 April 2017 • ideal • writeup

Yet another... cat service?!

yacs is a tool to store and later retrieve text snippets. If you store program source code there, it can even compile it for you! So handy. Of course, everything is protected using state-of-the-art user authorization and password hashing. It's a big C++ compiled binary which uses a local SQLite database file for data storage. Here's a normal create/list paste workflow: ___...