About Me

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Who Am I?

“Jonathan Zdziarski is considered, worldwide, to be among the foremost experts in iOS related digital forensics and security. As an iOS security expert in the field (sometimes known as the hacker “NerveGas”), Jonathan’s research into the iPhone has pioneered many modern forensic methodologies used today, and has been validated by the United States’ National Institute of Justice. Jonathan has extensive experience as a forensic scientist and security researcher specializing in reverse engineering, research and development, and penetration testing, and has performed a number of red-team penetration tests for financial payment processors, government agencies, and the military. Jonathan frequently consults with law enforcement agencies / military on high profile cases and assists federal, state and local agencies in their forensic investigations, and has trained many federal, state and local agencies internationally. Also an author for O’Reilly Media, Jonathan has written several books related to the iPhone including iPhone Forensics, iPhone SDK Application Development, iPhone Open Application Development, and his latest book, Hacking and Securing iOS Applications.”

  • … Forensic scientist and penetration tester (I develop new forensic techniques, I hack banks, government systems, and help solve cases for a living). I am also an experienced iOS / OSX application penetration testing consultant.
  • … Author of many books about the iPhone and Machine Learning, and still heavily involved in reverse engineering, security research, forensic tools development, and general hacking as part of my professional responsibilities.
  • … Educator, I teach a number of hands-on forensic science and penetration classes to law enforcement, government, military, and private organizations internationally.
  • … Former member of the iPhone Dev-Team, and worked on a number of jailbreak exploits between 2007-2009 ranging from the very first jailbreak of v1.0 to about 3.1.3.
  • … Creator of a suite of the first ever iOS Forensics Tools, which have been validated by the National Institute of Justice, and are used by over 2,000 law enforcement agencies worldwide (I also provide a large amount of consulting to various law enforcement agencies for various types of cases)
  • Subject matter expert and key contributor to the CompTIA iOS Secure Developer Certification
  • … Author of the free AMBER Alert iPhone application used by the National Center of Missing and Exploited Children
  • … Author of many popular App Store apps including Ballistic and iErase
  • … Author of Nescaline, a Nintendo emulator for iOS
  • … Original author of the popular DSPAM adaptive language classifier
  • … Member of IACIS, HTCC, and InfraGard
  • … That guy who got to shoot Al Capone’s Machine Gun, shoot hand guns in Canada, stay up all night working on murder cases with a bunch of canucks, and do other cool things.
  • … The hacker most people know as NerveGas.

The Hacker in Me


I’ve been hacking since age 8 and have come to develop very strong interests in reverse engineering, machine learning, cellphone hacking, and any other geek-worthy hacker projects I come across. My first PC was a TRS-80 with a cassette deck (no disk drives) and a whopping 128×48 B/W resolution. I recall bootlegging cheezy games from other TRS-80s in grade school, but consistently forgot about the lead track on the tape, and ended up with mostly worthless cassettes. My sister eventually paper mached the entire computer, rendering it completely unusable and also happened to void the ridiculously conservative warranty. Today I spend much of my hacker cycles working in the fields of reverse engineering and penetration testing, machine learning, mobile forensics, teaching, and writing. You can check out some of my brain children in the projects section.

The Author in Me


I took up writing when I was in grade school, but nobody really mentioned I was good at it, and so it faded away as I moved onto other things. I was approached a few years ago about writing a book covering the inner-clockwork of statistical spam filters like my DSPAM, and decided to give the pen another try. It seemed to turn out alright, and shortly thereafter I became inspired to write again on a more regular basis. I’ve recently finished a fifth book with O’Reilly Media, and have apparently found a good niche. One of the things I noticed was that good writers seemed to enjoy writing, whether or not they became famous for it. Paul Graham’s essays on life particularly inspired me by reminding me that I enjoyed writing. This philosophy seems to work for just about anything else in life too: if you enjoy it, spend a lot of time doing it, regardless of whether it makes you famous or pays the bills. I’ll occasionally pen an essay about some subject I feel passionate about. You can read some of these in my papers section.

The Musician in Me


Music (noun): brief interruptions between bass solos

I took up bass guitar when I was around 18, which came about by some cosmic mistake when a so-called friend of mine tried to dump his gear on me for some cash. It was a beat up Peavy Foundation, and I spent several months with bleeding fingers figuring out how the stupid thing worked. As it turned out, I started to enjoy it, and have been playing bass for the past 17 years, with only a few brief vacations. I didn’t “get” music theory until I really started playing the bass. Prior to that, I was so oblivious to music that my high school theory teacher (Mr. Metivier) beamed a book at my head and nearly got himself fired. I finally figured it out, though, and while hackers and painters are a more well known combination, hackers and musicians have more fun. They say music is sound that makes sense; I like Vic Wooten’s philosophy that music is a “language”, and like any other language, the most important thing is “having something to say”; having something written on your heart to express in music is an intimate thing, which is one way musicians differ from hackers in some ways, yet share together in others. As far as gear is concerned, I’ve since sworn off Peavy and other cheap store-bought hardware. I liked Fender up until they bought and trashed my favorite company at the time – Guild – who made me an amazing sounding Pilot Pro-5 Studio fretless bass, which I regret selling every day of my life. Since moving on, I’ve spent the past several years playing basses hand-crafted by JD Lewis at Warrior Instruments, which are probably the world’s finest and most playable instruments. I also play a pre-Gibson Tobias Signature 6-String, an amazing custom Mike Lull, and a few others. My musical inspirations have included Abraham Laboriel, John Patitucci, Anthony Sallee, Victor Wooten, Bootsy Collins, and many others. I still frequently listen to old tracks from Parliament, James Brown, and Brothers Johnson to name a few. On a Sunday, you’re more likely than not to find me playing in a church somewhere.

The Hacker in Me


During my time as a hacker, I found inventing new things to be much more interesting than the actual hackery itself. I also discovered an interesting parallel between the dangerous “experiments” hackers perform and the even more dangerous experiments that scientists do. Several years went by doing my own research and coming up with my own new ideas, some of which I’ve had the pleasure of lecturing on. In December 2009, I accepted an engineering position with a federally funded research and development center (FFRDC), and have since worked on many projects closely touching the government and/or finance sector. I work a lot of R&D at my present job, and also do a lot of penetration testing. We’re working on some of the coolest technologies to solve complex national security challenges. Research, invention, and experimentation seem to be my cup of tea. I gave a talk on some recent work during my fourth speaking engagement at the MIT SpamConference a while back, and have since been working on some great new R&D.

The Christian in Me


One thing I am undeniably certain about is my faith. When I made the decision to become a Christian, all of my former interests paled in comparison. I find the manuscripts surrounding the Biblical texts we use today to be by far the most beautiful logic I’ve ever read, and the God I believe in to be quite real and revealing to those who are willing to believe in Him. “Who I am” can’t possibly be expressed adequately without sharing my Christian faith, as it’s not only shaped my character but brought a new level of insight into my life. I spent my younger years just assuming the church was something people created to feel good about themselves. When I got a real perspective of what difference God made in the lives of people around me, it moved me to find out more.

I’ve spent several years lately studying church government and what the real church was originally supposed to look like. I ended up teaching myself the Greek language so I could read many manuscripts on parchment and see just how much mainstream theology was concoted by preachers in expensive suits. I concluded that most churches fall into one of two schools of thought: they’re either cheapened by the American culture engine and have compromised their faith to appeal to the masses, or have gone off on some apostolic power trip that was greatly exaggerated and have compromised their faith to appeal to their own ego. What bothers me most is that neither class seems to care one way or another about representing the true church, which I think is why so many people have such a strong aversion to it: I don’t think most of America has really seen what the real church was like. Fortunately, the God I worship still loves us, even in our ignorance, and in spite of ourselves, we are still forgiven.

Today, I’m sure many of my Christian beliefs would get me burned at the stake, but I’m not going back to my old, dead life, and am occasionally amused by the ignorance of the few who discredit my accomplishments by my belief in God.

Other Interests


In addition to my primary interests, I enjoy good music, Greek apocrypha, fine wine (a good bottle of Amarone della Valpolicella), and reading. My time in the South helped usher me into a fascination for firearms (and a love affair with freedom), and I enjoy the discipline of long-range rifle marksmanship. I’ve also been known to barbecue on occasion.

Professional Goals


I’m already doing what I love, and think I can see myself doing this type of work for a long time to come. My musical interests have got me interested in becoming a more proficient bassist and possibly getting into doing some studio work. However it pans out, I like having the experience to do the things I love and get paid for most of them. Life’s much too short to spend it not doing what you love.

Contacting Me


Although I write a lot of articles about different technologies, I don’t usually have time to answer many direct technical questions. I strongly recommend trying one of the mailing lists related to a particular project (such as dspam-users) or google before emailing me a technical question, because it runs a strong risk of ending up in the bit bucket. Sorry, but that’s just the way it has to be. You can also follow me on Twitter at @JZdziarski.

Aside from that, if you’d like to know more about my availability, my faith, or any other personal topics, please feel free to shoot me an email.

NOTE: I will not assist you with your iPhone unless you are law enforcement or military. No exceptions. Seriously. Stop emailing me with exception requests.

One Response to About Me

  1. Daniel Millions says:

    Just wanted to say that you have some great content on your blog. If it’s allowed I would like to use some of the information you provided on my blog. If I link back to your website do I have your permission to do so?

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