Category: Conferences


BSidesSF CTF: Choose your own keyventure: rsa-debugger challenge!

Thanks to symmetric (aka Brandon Enright) for this wonderful guest post! I tried to proofread it, but holy math Batman!! –Ron / @iagox86

Hey all, this is symmetric here! I was thrilled to be once again involved in running the BSidesSF CTF with such creative teammates and skilled CTF players.

My favorite challenge this year was rsa-debugger which, despite getting 12 solves, was actually quite hard. In this post I’d like to tell you a bit about the genesis of the challenge and how to solve it.

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BSidesSF CTF: Hard reversing challenge: Chameleon

For my third and final blog post about the BSidesSF CTF, I wanted to cover the solution to Chameleon. Chameleon is loosely based on a KringleCon challenge I wrote (video guide), which is loosely based on a real-world penetration test from a long time ago. Except that Chameleon is much, much harder than either.

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BSidesSF CTF: Easy to hard Rust reversing challenges

As mentioned in a previous post, I was honoured to once again help run BSidesSF CTF!

This is going to be a quick writeup for three challenges: config-me, rusty1, and rusty2. All three are reversing challenges written in Rust, although the actual amount of reversing required is low for the first two.

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BSidesSF CTF: Difficult reverse engineering challenge: Gman

Once again, it was my distinct privilege to be a BSidesSF CTF organizer! As somebody who played CTFs for years, it really means a lot to me to organize one, and watch folks struggle through our challenges. And more importantly, each person that comes up to us and either thanks us or tells us they learned something is a huge bonus!

But this week, I want to post writeups for some of the challenges I wrote. I’m starting with my favourite - Gman!

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In BSidesSF CTF, calc.exe exploits you! (Author writeup of launchcode)

Hey everybody,

In addition to genius, whose writeup I already posted, my other favourite challenge I wrote for BSidesSF CTF was called launchcode. This will be my third and final writeup for BSidesSF CTF for 2019, but you can see all the challenges and solutions on our Github releases page.

This post will be more about how I developed this, since the solution is fairly straight forward once you know how it’s implemented.

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Some crypto challenges: Author writeup from BSidesSF CTF

Hey everybody,

This is yet another author’s writeup for BSidesSF CTF challenges! This one will focus on three crypto challenges I wrote: mainframe, mixer, and decrypto!

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BSidesSF CTF author writeup: genius

Hey all,

This is going to be an author’s writeup of the BSidesSF 2019 CTF challenge: genius!

genius is probably my favourite challenge from the year, and I’m thrilled that it was solved by 6 teams! It was inspired by a few other challenges I wrote in the past, including Nibbler. You can grab the sourcecode, solution, and everything needed to run it yourself on our Github release!

It is actually implemented as a pair of programs: loader and genius. I only provide the binaries to the players, so it’s up to the player to reverse engineer them. Fortunately, for this writeup, we’ll have source to reference as needed!

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BSidesSF CTF wrap-up

Welcome!

While this is technically a CTF writeup, like I frequently do, this one is going to be a bit backwards: this is for a CTF I ran, instead of one I played! I’ve gotta say, it’s been a little while since I played in a CTF, but I had a really good time running the BSidesSF CTF! I just wanted to thank the other organizers - in alphabetical order - @bmenrigh, @cornflakesavage, @itsc0rg1, and @matir. I couldn’t have done it without you folks!

BSidesSF CTF was a capture-the-flag challenge that ran in parallel with BSides San Francisco. It was designed to be easy/intermediate level, but we definitely had a few hair-pulling challenges.

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SANS Hackfest writeup: Hackers of Gravity

Last week

A few weeks ago, SANS hosted a private event at the Smithsonian’s Air and Space Museum as part of SANS Hackfest. An evening in the Air and Space Museum just for us! And to sweeten the deal, they set up a scavenger hunt called “Hackers of Gravity” to work on while we were there!

We worked in small teams (I teamed up with Eric, who’s also writing this blog with me). All they told us in advance was to bring a phone, so every part of this was solved with our phones and Google.

Each level began with an image, typically with a cipher embedded in it. After decoding the cipher, the solution and the image itself were used together to track down a related artifact.

This is a writeup of that scavenger hunt. :)

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dnscat2: now with crypto!

Hey everybody,

Live from the SANS Pentest Summit, I’m excited to announce the latest beta release of dnscat2: 0.04! Besides some minor cleanups and UI improvements, there is one serious improvement: all dnscat2 sessions are now encrypted by default!

Read on for some user information, then some implementation details for those who are interested! For all the REALLY gory information, check out the protocol doc!

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BSides Winnipeg Wrap-up

For those of you who are close to me, you’ll know that my life has been crazy lately. Between teaching courses, changing jobs (here I come, Google!recently started at Google! (I’m slow at posting these :) )), and organizing BSides Winnipeg, I’ve barely had time to breathe!

Things are still chaotic, of course (in fact, movers were packing up my life as I wrote this), but I wanted to take some time and talk about BSides Winnipeg.

I’ll go over the background, the planning, the day-of, and some lessons learned. If you just want to see cool photos, here you go!

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Padding oracle attacks: in depth

This post is about padding oracle vulnerabilities and the tool for attacking them - “Poracle” I’m officially releasing right now. You can grab the Poracle tool on Github!

At my previous job — Tenable Network Security — one of the first tasks I ever had was to write a vulnerability check for MS10-070 — a padding oracle vulnerability in ASP.net. It’s an interesting use of a padding oracle vulnerability, since it leads to code execution, but this blog is going to be a more general overview of padding oracles. When I needed to test this vuln, I couldn’t find a good writeup on how they work. The descriptions I did find were very technical and academic, which I’m no good at. In fact, when it comes to reading academic papers, I’m clueless and easily frightened. But, I struggled through them, and now I’m gonna give you a writeup that even I’d be able to understand!

By the way, the Wikipedia page for this attack isn’t very good. If somebody wants to summarize my blog and make it into a Wikipedia page, there’s now a source you can reference. :)

On a related note, I’m gonna be speaking at Shmoocon in February: “Crypto: You’re doing it wrong”. Among other things, I plan to talk about padding oracles and hash extension attacks — I’m really getting into this crypto thing!

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Ethics of password cracking/dissemination

It’s rare these days for me to write blogs that I have to put a lot of thought into. Most of my writing is technical, which comes pretty naturally, but I haven’t written an argument since I minored in philosophy. So, if my old Ethics or Philosophy profs are reading this, I’m sorry!

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Faking demos for fun and profit

This week Last week Earlier this month Last month

Last year (if this intro doesn’t work, I give up trying to post this :) ), I presented at B-Sides Ottawa, which was put on by Andrew Hay and others (and sorry I waited so long before posting this… I kept revising it and not publishing). I got to give a well received talk, meet a lot of great folks, see Ottawa for the first time, and learn that I am a good solid Security D-lister. w00t!

Before I talk about the fun part, where I completely faked out my demo, if you want the slides you can grab them here: http://svn.skullsecurity.org:81/ron/security/2010-11-bsides-ottawa/. You can find more info about the conference and people’s slides at the official site. And finally, here’s a picture of me trying to look casual.

B-sides conferences, for those of you who don’t know, are awesome little conferences that often (but not always) piggyback on other conferences. They are free (or cheap), run by volunteers, and have raw and technical talks. B-sides Ottawa was no exception, and I’m thrilled I had the chance to not only see it, but take part in it. I really hope to run our own B-sides Winnipeg next year!

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Update on my life, conferences, career, etc

Hey all!

It’s been awhile since I’ve written on my blog, and I apologize. I’m at a job now where I actually spend my day working instead of pondering, so it’s hard to find time! :)

So, what’s new with me?

I’m working on some cool new Nmap stuff right now, so I’m hoping to write about that in the next couple months. Web application fingerprinting isn’t something I’ve seen done much, but I’m hoping Nmap can make some good progress on it with the help of Yokoso, Nikto, and some other resources.

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Who’s going to Shmoocon?

Hey everybody,

I’m heading to Shmoocon on Feb 4 - 8, so two things:

a) Who wants to meet up? I have plans on the Saturday, but not much else yet.

b) Please don’t hack me while I’m gone. ;)

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Toorcon Slides

Hey all,

Thanks for everybody who came out to my Toorcon talk! I had a great weekend, even the part where I got stuck in San Fransisco and spent two full days getting home. Oops :)

A couple people asked me if I’d put up my slides, so here you go: http://svn.skullsecurity.org:81/ron/security/2009-10-toorcon/2009-10%20Toorcon.pdf

(If you want the original OpenOffice format, directory listings are enabled on that server)

Thanks once again, and it was great to meet all of you!

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Toorcon coming up!

Hey all,

I’ll be presenting at Toorcon San Diego in a couple week (finalized lineup, my talk!).

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