Paweł Łukasik

challenge

Rusty

So I had my debut as an author of a task for a public CTF event. I've created a challenge called Rusty, and let's say it collected some mixed reactions. I've labeled it as an easy RE challenge, but only ten teams managed to

radare2

radare2 can do java

I was once asked on my YT channel to do a Java crackme. It only took 7* months to fulfill this request. So, wile waiting for Part 4, Professor this is for you. We will do a Java crack-me, but an easy one created by me. This is as I

resources

Ultimate list of resources for learning Reverse Engineering

It supposed to be the list of resources to learn Reverse Engineering but there's a lot of such lists already in the wild. So this post will sometimes list links of resources to learn RE - kind of meta. In no particular order: * https://hshrzd.wordpress.com/how-to-start/

ghidra

Automating Ghidra - part 2

In the last Automating Ghidra post we looked at how we can script Ghidra to do some mundane operations on the Memory Map of our binary. This time we will automate renaming labels for the data based on the values. During ASIS CTF 2020 a task was present that posses

pwntools

Making pwnlib.gdb.attach work under WSL2

I'm doing my CTFing under Windows. I used to spawn a VirtualBox or Hyper-V with Ubuntu from time to time when needed or used Digital Ocean's droplet but since WSL is in town and especially with the speed-up improvements that WSL2 brings I rarely do that.

security

Gynvael's challenges - Solutions to collection of small web security challs

Recently Gynvael started to post little web challenges that are around topics of web security with NodeJs/Express (mostly) and Flask. Since I used to participate actively in Missions (that you could see at the end of his streams) I was more than happy to participate in those challenges too.

ghidra

Automating ghidra

Ghidra is an awesome RE tool that quickly took off after its initial launch in 2019. It can display not only the disassembly of our binary but also have a decompiler that allows us to see a bit higher level code. You can also extend it by using python or

nes

Solving Space Fights CTF

Few months back I was solving a CTF challenge for the NES system. It was one of the Flare-On challenges for 2019. This time we will solve another one for the same system. A challenge named Space Fights CTF could be found on github along with the source code but

tamctf

TAMUCtf - leaning tower

There were multiple things wrong with this CTF but this one challenge was an interesting one. Windows binary, no noticeable entry point and no messages on screen. It's time to use our tools to dissect this one. Prefer watching? As usually, if possible, starting this task from running

debugging

Debugging .Net applications without source code with dotPeek Symbol Server

Few years ago I've made a video that demonstrates how one can debug (from Visual Studio) without having source code by using the dotPeek Symbol Server. You can see the video below: DotPeek is one of many competed .NET decompiler (I ❤ dnSpy) but it has a great feature

insomnihack

Kaboom!

This wasn't a difficult task but it had one tricky trick that made it took way more time than it should be required. We started with an exe file that when loaded in any disassembler tool (e.g. Ghidra) or do some preliminary checking to see that the

hitcon

Core Dumb - HitCon 2019

Note: challenge was solved together with Disconnected. Damn it my flag checker is so buggy it destroyed the program itself 😱 All I left is a core dump file :( Could you help me recover the flag ? Q_Q Let's start by checking the file that we are given in

lego

Hitcon 2019 Qualification - EV3 Arm

It's one of those challenges that brings together two things that I like - this time it was reverse engineering nad lego bricks. What was the input in this challenge was a picture that, supposedly depict how the robot was programmed and a rbf file that contains the

flare-on

Flare-On 2019 solutions/notes (upd. 11.02)

I'm well aware that there's multiple write-ups/solutions presenting 2019's Flare-On solutions but I've decided to provide my own for two reasons. Firstly, to have some notes I can easily find for future. Secondly, I think some of my solutions were non-standard

SEGA

Solving SEGA Genesis ROM CTF Challenge

File fot the challenge can be downloaded from here. In order to run the file we need an emulator. There are few available but I've used gens. Probably a better one could be found but at least for my purpose this was enough. After running gens and loading

reversing

Oldschool - CONFidence Teaser 2019

Gynvael did a survey lately to see what kind of assembly is taught in Polish universities, and if any of them is still teaching the old 8086. Let us extend this question to the CTF scene! This challenge is a clear reference to Gynvael's survey which is obvious

ctf

Never ever be fooled to pay ransomware!

— Has Your Android Phone Been Infected with Malware? — Yes! — It’s awful but we have a cure! #rev #forensics Solved together with: disconnect3d The challange was part of CTFZone 2018 Quals by BiZone. We are given a phonedump.zip.e87a72e6edd605e73ce49dc926fc6c87 file that after unzipping produces two files: backup.android and

radre2

Handling self-modifying​ code with radare2

This is a post that explains a little bit in details what was shown in the two videos that could be watched on my YT channel. If you haven't seen them and are not yet confused enough about I recommend go check them out. As they might not

gynvael

GynvaelEN - Mission 023 - Solution

Prefere videos? You can also watch it - if not, continue reading. Mission status: http://gynvael.vexillium.org/ext/43bf753f/mission023.txt We are given the package that consists of one .exe file and system.img. The .exe looks like a .NET application (default name for Console project is ConsoleApp1.

ctf

Stop KrkAnalytica - solution

NeverLeaks is in danger and your help is needed! An anonymous hacker reported that Krakow Analytica company had prepared some actions to sabotage a befriended producer of aircraft tanks - NeverLeaks. The sabotage campaign can be stopped only if you discover the secret codes, give an admin access to their

gynvael

Gynvael - Mission 22 - Solution

This was a hard one. Information about this mission can be found in stream #64 and the mission itself is here. It's in Polish but the most relevant information here is that there's a RISC-V firmware that needs to be analyzed and password to be extracted.

gynvael

GynvaelEN - Mission 022 - Solution

Blokchain. *Coin. Hot topis for today. The 22nd mission is about blokchain and about coins. SpyCoins. The mission can be found on Stream #49. The SpyCoin center is here: http://gynvael.coldwind.pl/mission022_spycoin/ First failed attempt I've tried to main SpyCoin. That would be an obvious

gynvael

Gynvael - Mission 021 - Solution

The source for this mission can be found in stream 63. It is in Polish but it can be easily spotted that the main source is a PCAP file that can be downloaded from here. Wireshark(ing) Hacing this file on our disk, there isn't much more to

gynvael

Finding "Praktyczna Inżyniera Wsteczna" last hidden flag.

If you read this blog you can see that from time to time I participate in missions published by Gynvael Coldwind on his English and Polish streams. You might not know that he is an author of 2 (one self, one co-op) books in the simillar topics that he presents

solution

Assembly job offer... "Follow the white rabbit" solution

In a cold Novemeber night I was standing at a bus stop and saw and advertisement on the streets of Wrocław. What was odd about it it was written purely in assembly. Ok, to tell you the truth I was nothing like that. In reallity I was just browsing through