GHIDRA for Reverse Engineering (PicoCTF 2022 #42 'bbbloat')

Help the channel grow with a Like, Comment, & Subscribe!
❤️ Support ➡ j-h.io/patreon ↔ j-h.io/paypal ↔ j-h.io/buymeacoffee
Check out the affiliates below for more free or discounted learning!
🖥️ Zero-Point Security ➡ Certified Red Team Operator j-h.io/crto
💻Zero-Point Security ➡ C2 Development with C# j-h.io/c2dev
👨🏻‍💻7aSecurity ➡ Hacking Courses & Pentesting j-h.io/7asecurity
📗Humble Bundle ➡ j-h.io/humblebundle
🐶Snyk ➡ j-h.io/snyk
🌎Follow me! ➡ j-h.io/discord ↔ j-h.io/twitter ↔ j-h.io/linkedin ↔ j-h.io/instagram ↔ j-h.io/tiktok
📧Contact me! (I may be very slow to respond or completely unable to)
🤝Sponsorship Inquiries ➡ j-h.io/sponsorship
🚩 CTF Hosting Requests ➡ j-h.io/ctf
🎤 Speaking Requests ➡ j-h.io/speaking
💥 Malware Submission ➡ j-h.io/malware
❓ Everything Else ➡ j-h.io/etc

[@micleh]

Liked that one, since it is an easy example of how to disassemble code and make sense of what is readable. Perfect as a beginner tutorial.

[@11ph22il]

These videos are the spam I like to get, each one with GREAT info on CTFs. Thanks John!

[@MikeDSutton]

In case anyone else was curious what the 'unscramble_flag' function did, here's the rough equivelent in Python 3: bytes([ b + (0x2F if b < 0x50 else -0x2F) for b in bytes([ 0x41, 0x3a, 0x34, 0x40, 0x72, 0x25, 0x75, 0x4c, 0x34, 0x46, 0x66, 0x30, 0x66, 0x39, 0x62, 0x30, 0x33, 0x3d, 0x5f, 0x63, 0x66, 0x30, 0x62, 0x65, 0x35, 0x35, 0x62, 0x60, 0x65, 0x32, 0x4e ]) ])

[@Lampe2020]

I first saw the code then the description you gave but I immediately recognized it as Python3-code because two of my last three Python3-projects involved exactly that, converting lists of numbers between 0x00 and 0xff to byte strings (`bytes` object) XD

[@kadericketts9218]

Been loving the PICO CTF videos you’ve been making have watch most of them and have been learning a lot as i am just a noob in IT

[@deltabytes]

I like the way you take us through step by step. I am learning a lot from these videos.

[@arr3business939]

same

[@DevBranch]

Thank you for making these videos! I'm new to this, so being able to see how this works first-hand is extremely helpful.

[@sk0r]

I’ll be honest, a lot of your videos I have no idea what you are doing, but I enjoy watching you and your skill set and what is possible with the right tools. 🙏

[@hardelectrolove]

Did you just accidentally release every video for the next weeks/months at once? Holy moly, that's a lot of stuff in my Watch Later playlist now! x)

[@VA3KAMA3]

same. just have had a marathon watching them

[@theamazingjay161]

Okay, so I'm not the only one.

[@HYPR.trophy]

I appreciate hearing your thought process as you go through the challenge

[@user-cl4gy7pi6q]

Man u r DANGEROUS! lol 🙃☺ keep ur great work up dude! 💪

[@Dex_Lulz]

The more spend I time on your channel the more I learn.

[@tpai302]

I'm so bad at RE but love watching others do it so I can pick up on little things each time.

[@jackscalibur]

Hey! Do you feel like you're better at it now?

[@1234enzor]

A flashback and relearning TY!

[@P-G-77]

Love this intricate logic tricks.

[@ronorocky]

i just love you man,you are just awesome....... hope someday i will meet u in person.... u r doing a great job... keep it up. ❤️❤️

[@kevinalexander4959]

Would love to see a video on rebasing. I have a hard time with alignment using strings. Would love a newbie friendly of you rebasing binaries that do not align in disassembler. thanks!!

[@HyBlock]

couldn't this be done in some other way, my feed is filled with all those uploads making it harder to browse, don't wanna unsubscribe cus I appreciate your work though!

[@TheJustinist]

Yep, unsubbed

[@KoskiK]

Quite the same, after the first burst of videos I figured it was just a mistake or an error with the scheduler. After this new one I unsubbed unfortunately, as I enjoyed the content. KZbin should by now have made a limit, say 3 posts of a single person in the sub feed.

[@ocoolwow]

@@KoskiK ah that would actually assume that KZbin would output usable work

[@zdrasbuytye]

You can do reverse engineering with the Linux shell only .

[@kr4k3nn]

This is my first time seeing Reverse Engineering. I am like WOW, this is so fun to watch & do. THanks John for introducing this very interesting things to us. :)

[@for14556]

Very nice video about rev, thx.

[@Riiveri]

I have no idea why KZbin decided to recommend me these videos but I'm glad it did. This is awesome!

[@vivarantx]

same here, I was watching people eating 30 bags of cheetos and I ended up here

[@kiizuha]

@@vivarantx lmao

[@mytechnotalent]

Love me some Ghidra!

[@FakeMichau]

KZbin after seeing so many uploads: i'm gonna end this man's whole career

[@inazumaeleven9102]

I like the fact that in each ctf videos, I learn new tools to use for hacking. Now I check the bell icon. Keep on going man, u the best

[@ancestrall794]

Awesome bro

[@sem8973]

This would have been a perfect intro tutorial to reverse engineering with Ghidra

[@KGAD0831]

I really liked this one.

[@aurelienlevra3782]

Great video

[@SamoCoder]

This was interesting. Liked and subscribed.

[@tech-wandeveloper7495]

That was cool man!

[@cod4volume]

As far as open source content goes, John, you’re an OG. A goat. Appreciate the content and knowledge dude, stay humble.

[@gogogg91]

Awesome!

[@nightst0rm230]

hello sir your videos are great it helped me for solving and understanding all the ctfs of thm

[@victorkuria4734]

Great stuff

[@lancemarchetti8673]

Hi John, can you please review "angr" for us. I don't have a clue where to start...lol

[@bkib]

Nice!

[@DanjumaMuhammad]

I like the term "low-hanging fruit 🍓" 😊

[@wonderweissmargela4261]

Easy with the upload sir

[@makayjozsef]

You can use "apt search" too for package searching

[@lancemarchetti8673]

agreed

[@noodlechan_]

what if we reverse engineer Ghidra binarys using GHidra?

[@msalih]

Awesome

[@yttos7358]

Another way of converting from hex to decimal is with the `printf` command which can be found on any linux system; use `printf %d 0xc0ffee` to see

[@skeeberk.h.4396]

Very Nice

[@WayneModz]

I guess its kinda good you didn't have the environment requirements preinstalled

[@abiodun6897]

i got it 🙋🏾‍♂️. where can i learn this reverse engineering

[@polinimalossi8404]

but you can make the same video with the imusic aimersoft program?

[@user-zo1kn8ob7h]

oh look a user agreement, "i agree" never to be thought of again

[@m4rt_]

6:20 (sdkman is a good tool for downloading java stuff)

[@user-no5vf3kn9l]

Headless for Java means its stripped of mouse and keyboard input libraries and whatnot. Badly breaks java swing, so you probably don't want to use that.

[@user-he9uj1lr1k]

Please 🙏 sir can I use this to do reverse engineering on my mobile app??? Can someone help me out

[@krish12180]

Nice one

[@Walker-hh7xf]

you should also check out cutter

[@ashokshastri9101]

Sir big fan of yours from Lamatol village, golbazar-06 municipality, siraha district, sagarmatha zone, Madhesh Pradhesh (province no 2), nepal 🇳🇵

[@codedsprit]

I wish I had a nice laptop like yours 🥺

[@superfish4603]

There are 11 hidden videos in the playlist, when do we get them? :)

[@cryproot9845]

It's a good video

[@znucii]

MAHYOUB WE MISS YOU

[@passaronegro349]

...would it be possible to have subtitles in Portuguese ???

[@untitled8027]

nice

[@tribblewing]

My etc/apt/sources.list is using Kali Linux's default repo, but I can only install strace. ltrace keeps getting an error: "Unable to locate package". Has anyone figured out a working alternative repo?

[@heisenberg8055]

TF I just watched! Interesting

[@TheofilosMouratidis]

at 13:26 you already got the decimal by hovering over the number

[@MrLetsGamePlayHD]

In ghidra you can also change the display type

[@Lampe2020]

The word "Bbbbbbbloat" is a bloated word and has the same effect as a mass of bloatware has on a PC: it works, but slower.

[@tlocto]

can't wait till you go over noted, was my favorite one

[@vinnie3265]

Everytime I Try to run a binary file on my kali linux I am getting exec format error...so I am not able to solve any rev engineering problems....can someone plss help with it🙏🙏🙏🙏

[@MisterK-YT]

John can you post the code that formats your bash (or zsh) prompt? From your .bashrc or wtvr config file. I like that two-line prompt.

[@Mathcartney]

Its zsh the shell that he uses, it isn’t bash. And the theme is the default kali theme. There are many other custom themes and wrappers such as powerlevel10k if you dig it deeper tho

[@mikerich5003]

Has anyone on bohemia has their initial deposit asst changed..

[@faxhack]

Wait this is intresting

[@Bowzerbro]

👍

[@wahabwahab2042]

im watching your video and honestly i'm 80% didn't understand what are you doing exactly. i wonder what level is that ? im sure it is advanced level . where to start to achieve your level ??

[@leblanc666666]

nice and simple, but fun nonetheless! Does picoCTF have have challenges that are more based on web applications?

[@iKilleasy007]

picoCTF has a web exploitation category

[@AliYar-Khan]

Can we reverse engineer malware and then remove them this way ?

[@bmbiz]

That's pretty much the _only_ way to remove previously unknown malware: reverse engineer it, figure out all changes it makes and then undo all those changes on an infected system.

[@marcoamendoza5283]

Does anyone have the bbbblob file to try it out?

[@Bromon655]

What is the Linux wizardry… dude was flying through the terminal like nobody’s business

[@SultanSaadat]

can you send us your shell modifications? This looks so cool.

[@MasterRg-cj7tt]

Hi , I am new PicoCTF . and i try to solve that for practice if i cant i am looking for in google for solving . But I cant find picoCTF notepad Author: ginkoid . Can you help me? How can i solve that

[@afrkleaks4991]

I do not have time with all these load it opens this read there and there then crack it i refuse all these stuff at the end you have to find the way to get in to the software, easy ways quickly just load malware to infect

[@anujsrivastav6444]

Hey jhon can you please tell me how I can trace the memory leak from heapdump file?

[@roachxyz]

What is this stuff called? Cybersecurity?

[@NexushasTaken]

its already in the video title.

[@MygenteTV]

wtf, this is weird I had been watching your videos and even follow you in LinkedIn for years and just found out I wasn't subscribed to your channel. KZbin be playing tricks, they welcome you with your favorite channel for ever and you will never know you weren't subscribed because everytime you open youtube and see the same person there you automatically think you are subscribed

[@mideno7619]

Sup

[@MisterK-YT]

Question: why didn’t he “trust” the Ghidra from the official Kali repo? Why go through the process of installing manually??

[@SheIITear]

Stuff from the repos on your distro tend/might be really old. In case of ghidra you just download and extract it so thats the fastest way to get the latest.

[@MisterK-YT]

@@SheIITear noted! Thanks!

[@vaisakhkm783]

I wanted to ask same. I thought it might be the reason but to make sure... Is that a problem with distros like fedora or arch!?... those are more up to date than Debi an right!?

[@patrickborys3490]

ez

[@metsfaninct]

Man, nothing like getting spammed. Should have spaced it out.

[@ocoolwow]

You gotta stop man, this is flooding my sub box

[@pitust]

process or RE with binary ninja: step 1: load the binary. step 2: see the number in plain text from the decompiler. step 3: profit

[@KirwinWebb]

You seemed disappointed that you got the flag so quickly.

[@utensilapparatus8692]

John 1337 the king

[@WaseemLaghari]

I solve it by viewing your video but you did it late by looking for other stuffs. Maybe you do to let us all understand everything

[@ultimultig]

cool but i didn't understand a single word said in this video

[@kraemrz]

Yt algo

[@BigWin24410]

Is this the apparently kid all grown up?

[@CodyHoskin]

Have you ever got a live virus on your own system? Or a RAT?

[@bohu3741]

its too simple

[@fatizahra3420]

m9wd

[@nguyentrang7909]

beautiful hair ........ I want to touch it haha

[@onizuka2345]

Removed from my feed for uploading 18 videos at a time. You know how KZbin works and that is not how you do it.

[@ocoolwow]

Bye don't let the door hit you on the way out

[@musa4213]

why your voice like ill man, my tonsil hurts now AAAH

[@OkOkOkIMightKnowYou]

High Level Forgetting

[@infernez]

I gotta unsub for a little bit until this wave is finished with. You are absolutely flooding my subscribe stream.

[@zxCraig1690Xz]

You my friend just got an unsub for those stupid uploads spamming my feed👺