Tuesday, February 23, 2021

Book Review: "This Is How They Tell Me the World Ends"

This blog post is a review of the book "This Is How They Tell Me the World Ends" by Nicole Perlroth. The book tries to shed light on the "zero day market" and how the US government interacts in this market, as well on various aspects of nation-to-nation "cyberwarfare".

I was excited to see this book come out given that there are relatively few hats in this field I have not worn. I have worked in information security since the late 1990's; I was part of a youth culture that playfully pioneered most of the software exploitation techniques that are now used by all major military powers. I have run a business that sold technology to both defenders and offensive actors. I have written a good number of exploits and a paper clarifying the theoretical foundations for understanding them. I have trained governments and members of civil society on both the construction and the analysis of exploits, and on the analysis of backdoors and implants. I have spent several months of my life reading the disassembled code of Stuxnet, Duqu, and the Russian Uroburos. I spent half a decade at Google on supporting Google's defense against government attackers; I spent a few additional years in Project Zero trying to nudge the software industry toward better practices. Nowadays, I spend my time on efficiency instead of security.

I have always been close to, but never part of, the zero-day market. My background and current occupation give me a deep understanding of the subject, while not tying me economically to any particular perspective. I therefore feel qualified like few others to review the book.

"This Is How They Tell Me the World Ends" tackles an important question: What causes the vulnerability of our modern world to "cyberattacks"? Some chapters cover various real-world cyberattacks, some chapters try to shed light on the "market for exploits", and the epilogue of the book discusses ideas for a policy response.

The author managed to get access to a fantastic set of sources. Many things were captured on the record that were previously only discussed on background. Several chapters recount interviews with former practitioners in the exploit market, and these chapters provide a glimpse into the many fascinating and improbable personalities that make up the field. This is definitely a strong asset of the book.

Given the exciting and impactful nature of the "cyberwar" subject, the many improbable characters populating it, and the many difficult and nuanced policy questions in the field, the level of access and raw material the author gathered could have been enough for a fantastic book (or even two).

Unfortunately, "This Is How They Tell Me the World Ends" is not a fantastic book. The potential of the source material is diluted by a large number of inaccuracies or even falsehoods, a surprising amount of ethnocentricity and US-American exceptionalism (that, while being a European, I perceived to border on xenophobia), a hyperbolic narration style, and the impression of facts bent to support a preconceived narrative that has little to do with reality.

For the layperson (presumably the target audience of this book) the many half-truths and falsehoods make the book an untrustworthy guide to an important and difficult topic. For the expert, the book may be an entertaining, if jarring read, provided one has the ability to dig through a fair bit of mud to find some gold. I am confident that the raw material must be great, and where it shines through, the book is good.

Inaccuracies and Falsehoods

The topic is complex, and technical details can be difficult to get right and transmit clearly. A book without any errors cannot and should not be expected, and small technical errors should not concern the reader. That said, the book is full of severe and significant errors - key misunderstandings and false statements that are used as evidence and to support conclusions - and those do raise concerns.

I will highlight a few examples of falsehoods or misleading claims. I only found those falsehoods that overlapped with expertise of mine; extrapolating from this, I am afraid that there may be many more in the book.

The following examples are from the first third of the book; and they are illustrative of the sort of mistakes throughout: Facts are either twisted or exaggerated to the point of becoming demonstrably false; and these twists and exaggerations seem to always happen in support of a narrative that places an unhealthy focus on zero-days.

First, one of the more egregious falsehoods is the claim that NSA hacked into Google servers to steal data:

... the agency hacked its way into the internal servers at companies like Google and Yahoo to grab data before it was encrypted.
This simply did not happen. As far as anyone in the industry knows, in the case of Google, unencrypted network connections between datacenters were tapped. This may sound inconsequential, but undermines the central "zero days are how hacking happens" theme of the book.

Second, the entire description of zero-days is full of false claims and hyperbole:
Chinese spies used a single Microsoft zero-day to steal some of Silicon Valley's most closely held source code.
This alludes to the Aurora attacks on Google; but anyone that knows Google's internal culture knows that source code is not most closely held by design. Google always had a culture where every engineer could roam through almost all the code to help fix issues.
...Once hackers have figured out the commands or written the code to exploit it, they can scamper through the world's computer networks undetected until the day the underlying flaw is discovered
This is simply not true. While a zero-day exploit will provide access to a given machine or resource, it is not a magic invisibility cloak. The Chinese attackers were detected, and many other attackers are routinely detected in spite of having zero-day exploits.
...Only a select few multinationals are deemed secure enough to issue the digital certificates that vouch (...) that Windows operating system could trust the driver  (...) Companies keep the private keys needed to abuse their certificates in the digital equivalent of Fort Knox.
This section is at best misleading: The driver in question was signed with a stolen JMicron "end-entity" certificate. There are thousands of those, all with the authority to sign device drivers to be trusted, and the due diligence to issue one used to be limited to providing a fax of an ID and a credit card number.

The "select few multinationals" Perlroth writes about here are the certificate authorities that issue such "end-entity" certificates. It is true that a CA is required to keep their keys on a hardware security module (a very high-security setup), and that the number of CAs that can issue driver-signing certificates is limited (and falling).

The text makes it appear as if a certificate from a certificate authority (and hence from a hardware security module) had been stolen. This is simply false. End-entity certificates are issued to hardware vendors routinely, and many hardware vendors play fast and loose with them.

(It is widely rumored - but difficult to corroborate - that there used to be a thriving black market where stolen end-entity certificates were traded a few years ago; the going rate was between $30k and $50k if I remember correctly.

Ethnocentricity and US exceptionalism

As a non-US person, the strangest part of the book was the rather extreme ethnocentricity of the book: The US is equated with "respecting human rights", everything outside of the US is treated as both exotic and vaguely threatening, and the book obsesses about a "capability gap" where non-US countries somehow caught up with superior US technology.

This ranges from the benign-but-silly (Canberra becomes the "outback", and Glenn Greenwald lives "in the jungles of Brazil" - evoking FARC-style guerillas, when - as far as I am informed - he lives in a heavily forested suburb of Rio) to seriously impacting and distorting the narrative.

The author seems to find it unimaginable that exploitation techniques and the use of exploits are not a US invention. The text seems to insinuate that exploit technologies and "tradecraft" were invented at NSA and then "proliferated" outward to potentially human-rights-violating "foreign-born" actors via government contractors that ran training classes.

This is false, ridiculous, and insulting on multiple levels.

First off, it is insulting to all non-US security researchers that spent good parts of their lives pioneering exploit techniques.

The reality is that the net flow of software exploitation expertise out of NSA is negative: Half a generation of non-US exploit developers migrated to the US over the years and acquired US passports eventually. The US exploit supply chain has always been heavily dependent on "foreign-born" people. NSA will enthusiastically adopt outside techniques; I have yet to learn about any exploitation technique of the last 25 years that "leaked" out of NSA vs. being invented outside.

The book's prologue, when covering NotPetya, seems to imply that Russia had needed the Shadowbrokers leaks - ("American weapons at its disposal") - to cause severe damage. Anybody with any realistic visibility into both the history of heap exploitation and the vulnerability development community knows this to be absolutely wrong.

Secondly, it seems to willfully ignore recent US history with regards to human rights. Somehow implying that the French police or the Norwegian government have a worse human rights track record than the US government - which unilaterally kills people abroad without fair trial via the drone-strike program, relatively recently stopped torturing people, and keeps prisoners in Guantanamo for 15+ years by having constructed a legal grey zone outside of the Geneva Conventions - is a bit rich.

In the chapter on Argentina, Ivan Arce calls the author out on her worldview (which was one of my favorite moments in the book), but this seems to have not caused any introspection or change of perspective. This chapter also reveals an odd relationship to gender: The narrative focuses on men wreaking havoc, and women seem to exist to rein in the out-of-control hackers. Given that there are (admittedly few, but extremely capable) women and non-binary folks active in the zero-day world, I find this narrative puzzling.

There is also an undercurrent that everything bad is caused by nefarious foreign intervention: The author expresses severe doubts that the 2016 US election would have had the same outcome without "Russian meddling", and in the Epilogue writes "it is now easier for a rogue actor to (...) sabotage (...) the Boeing 737 Max", somehow managing to link a very US-American management failure to vague evil forces.

In its centricity on the US and belief in US exceptionalism, its noticeable grief about the 2016 US election, and the vague suspicion that everything bad must have a foreign cause, the reader learns more about the mindset of a certain subset of the US population than about cybersecurity or cyberwarfare.

Hyperbolic language

The book is also made more difficult to read by constant use of hyperbolic language. Exploits are capable of "crashing Spacecraft into earth", "detonated to steal data", and things always need to be "the most secure", "the most secret", and so forth. The book would have benefitted from the editor-equivalent of an equalizer to balance out the wording.

The good parts

There are several things to like about the book: The chapters that are based on interviews with former practitioners are fun and engaging to read. The history of software exploits is full of interesting and unorthodox characters, and these chapters provide a glimpse into their world and mindsets.

The book also improves as it goes on: The frequency of glaring falsehoods seems to decrease - which lets the fact that it is generally engaging come through.

Depending on what one perceives the thesis of the book to be, one can also argue that the book advances an important point. The general subject - "how should US government policy balance offensive and defensive considerations" - is a deep and interesting one, and there is a deep, important, and nuanced discussion to be had about this. If the underlying premise of the book is "this discussion needs to be had", then that is good. The book seems to go much beyond this (reasonable) premise, and seems to mistakenly identify the zero-day market as the root cause of pervasive insecurity.

As a result, the book contributes little of utility to a defensive policy debate. The main drivers of the cyber insecurity are hardly discussed until the Epilogue: The economic misincentives that cause the tech industry to earn hundreds of billions of dollars from creating the vulnerabilities in the first place (for every million earned through the sale of exploits, an order of magnitude or two more is earned through the sale of the software that creates the security flaw), and the organisational misincentives that keep effective regulation from arising (NSA - rightly - has neither mission or authority to regulate the tech industry into better software, so accusing them of not doing so is a bit odd). By placing too much emphasis on governments knowing about vulnerabilities, the book distracts from the economic forces that create a virtually infinite supply of them.

The Epilogue (while containing plenty to disagree with) was one of the stronger parts of the book. The shortness makes it a bit shallow, but it touches on many points that warrant a serious discussion. (Unfortunately, it again insinuates that "ex-NSA hackers tutor Turkish Generals in their tradecraft"). If anything, the Epilogue can be used as a good (albeit incomplete) list of topics to discuss in any cybersecurity policy class.

Concluding thoughts

I wish the book realized more of the potential that the material provided. The debate about the policy trade-offs for both offense and defense needs to be had (although there is less of a trade-off than most people think: Other countries have SIGINT agencies that can do offense, and defensive agencies focused on improving the overall security level of society; fixing individual bugs will not fix systemic misincentives), and a good book about that topic would be very welcome.

Likewise, a book that gives a layperson a good understanding of the zero-day trade and the practitioners in the trade would be both useful and fascinating.

The present book had the potential to become either of the above good books - the first one by cutting large parts of the book and expanding the Epilogue, the second one by rigorous editing and sticking to the truth.

So I regret having to write that the present book is mostly one of unfulfilled potential, and that the layperson needs to consult experts before taking any mentioned "fact" in the book at face value.

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