Tag Archives: cryptowars

Scaring People into Supporting Backdoors

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/12/scaring_people_.html

Back in 1998, Tim May warned us of the “Four Horsemen of the Infocalypse”: “terrorists, pedophiles, drug dealers, and money launderers.” I tended to cast it slightly differently. This is me from 2005:

Beware the Four Horsemen of the Information Apocalypse: terrorists, drug dealers, kidnappers, and child pornographers. Seems like you can scare any public into allowing the government to do anything with those four.

Which particular horseman is in vogue depends on time and circumstance. Since the terrorist attacks of 9/11, the US government has been pushing the terrorist scare story. Recently, it seems to have switched to pedophiles and child exploitation. It began in September, with a long New York Times story on child sex abuse, which included this dig at encryption:

And when tech companies cooperate fully, encryption and anonymization can create digital hiding places for perpetrators. Facebook announced in March plans to encrypt Messenger, which last year was responsible for nearly 12 million of the 18.4 million worldwide reports of child sexual abuse material, according to people familiar with the reports. Reports to the authorities typically contain more than one image, and last year encompassed the record 45 million photos and videos, according to the National Center for Missing and Exploited Children.

(That’s wrong, by the way. Facebook Messenger already has an encrypted option. It’s just not turned on by default, like it is in WhatsApp.)

That was followed up by a conference by the US Department of Justice: “Lawless Spaces: Warrant Proof Encryption and its Impact on Child Exploitation Cases.” US Attorney General William Barr gave a speech on the subject. Then came an open letter to Facebook from Barr and others from the UK and Australia, using “protecting children” as the basis for their demand that the company not implement strong end-to-end encryption. (I signed on to another another open letter in response.) Then, the FBI tried to get Interpol to publish a statement denouncing end-to-end encryption.

This week, the Senate Judiciary Committee held a hearing on backdoors: “Encryption and Lawful Access: Evaluating Benefits and Risks to Public Safety and Privacy.” Video, and written testimonies, are available at the link. Eric Neuenschwander from Apple was there to support strong encryption, but the other witnesses were all against it. New York District Attorney Cyrus Vance was true to form:

In fact, we were never able to view the contents of his phone because of this gift to sex traffickers that came, not from God, but from Apple.

It was a disturbing hearing. The Senators asked technical questions to people who couldn’t answer them. The result was that an adjunct law professor was able to frame the issue of strong encryption as an externality caused by corporate liability dumping, and another example of Silicon Valley’s anti-regulation stance.

Let me be clear. None of us who favor strong encryption is saying that child exploitation isn’t a serious crime, or a worldwide problem. We’re not saying that about kidnapping, international drug cartels, money laundering, or terrorism. We are saying three things. One, that strong encryption is necessary for personal and national security. Two, that weakening encryption does more harm than good. And three, law enforcement has other avenues for criminal investigation than eavesdropping on communications and stored devices. This is one example, where people unraveled a dark-web website and arrested hundreds by analyzing Bitcoin transactions. This is another, where policy arrested members of a WhatsApp group.

So let’s have reasoned policy debates about encryption — debates that are informed by technology. And let’s stop it with the scare stories.

EDITED TO ADD (12/13): The DoD just said that strong encryption is essential for national security.

All DoD issued unclassified mobile devices are required to be password protected using strong passwords. The Department also requires that data-in-transit, on DoD issued mobile devices, be encrypted (e.g. VPN) to protect DoD information and resources. The importance of strong encryption and VPNs for our mobile workforce is imperative. Last October, the Department outlined its layered cybersecurity approach to protect DoD information and resources, including service men and women, when using mobile communications capabilities.

[…]

As the use of mobile devices continues to expand, it is imperative that innovative security techniques, such as advanced encryption algorithms, are constantly maintained and improved to protect DoD information and resources. The Department believes maintaining a domestic climate for state of the art security and encryption is critical to the protection of our national security.

Former FBI General Counsel Jim Baker Chooses Encryption Over Backdoors

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/10/former_fbi_gene.html

In an extraordinary essay, the former FBI general counsel Jim Baker makes the case for strong encryption over government-mandated backdoors:

In the face of congressional inaction, and in light of the magnitude of the threat, it is time for governmental authorities­ — including law enforcement­ — to embrace encryption because it is one of the few mechanisms that the United States and its allies can use to more effectively protect themselves from existential cybersecurity threats, particularly from China. This is true even though encryption will impose costs on society, especially victims of other types of crime.

[…]

I am unaware of a technical solution that will effectively and simultaneously reconcile all of the societal interests at stake in the encryption debate, such as public safety, cybersecurity and privacy as well as simultaneously fostering innovation and the economic competitiveness of American companies in a global marketplace.

[…]

All public safety officials should think of protecting the cybersecurity of the United States as an essential part of their core mission to protect the American people and uphold the Constitution. And they should be doing so even if there will be real and painful costs associated with such a cybersecurity-forward orientation. The stakes are too high and our current cybersecurity situation too grave to adopt a different approach.

Basically, he argues that the security value of strong encryption greatly outweighs the security value of encryption that can be bypassed. He endorses a “defense dominant” strategy for Internet security.

Keep in mind that Baker led the FBI’s legal case against Apple regarding the San Bernardino shooter’s encrypted iPhone. In writing this piece, Baker joins the growing list of former law enforcement and national security senior officials who have come out in favor of strong encryption over backdoors: Michael Hayden, Michael Chertoff, Richard Clarke, Ash Carter, William Lynn, and Mike McConnell.

Edward Snowden also agrees.

EDITED TO ADD: Good commentary from Cory Doctorow.

Attorney General William Barr on Encryption Policy

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/07/attorney_genera_1.html

Yesterday, Attorney General William Barr gave a major speech on encryption policy — what is commonly known as “going dark.” Speaking at Fordham University in New York, he admitted that adding backdoors decreases security but that it is worth it.

Some hold this view dogmatically, claiming that it is technologically impossible to provide lawful access without weakening security against unlawful access. But, in the world of cybersecurity, we do not deal in absolute guarantees but in relative risks. All systems fall short of optimality and have some residual risk of vulnerability a point which the tech community acknowledges when they propose that law enforcement can satisfy its requirements by exploiting vulnerabilities in their products. The real question is whether the residual risk of vulnerability resulting from incorporating a lawful access mechanism is materially greater than those already in the unmodified product. The Department does not believe this can be demonstrated.

Moreover, even if there was, in theory, a slight risk differential, its significance should not be judged solely by the extent to which it falls short of theoretical optimality. Particularly with respect to encryption marketed to consumers, the significance of the risk should be assessed based on its practical effect on consumer cybersecurity, as well as its relation to the net risks that offering the product poses for society. After all, we are not talking about protecting the Nation’s nuclear launch codes. Nor are we necessarily talking about the customized encryption used by large business enterprises to protect their operations. We are talking about consumer products and services such as messaging, smart phones, e-mail, and voice and data applications. If one already has an effective level of security say, by way of illustration, one that protects against 99 percent of foreseeable threats is it reasonable to incur massive further costs to move slightly closer to optimality and attain a 99.5 percent level of protection? A company would not make that expenditure; nor should society. Here, some argue that, to achieve at best a slight incremental improvement in security, it is worth imposing a massive cost on society in the form of degraded safety. This is untenable. If the choice is between a world where we can achieve a 99 percent assurance against cyber threats to consumers, while still providing law enforcement 80 percent of the access it might seek; or a world, on the other hand, where we have boosted our cybersecurity to 99.5 percent but at a cost reducing law enforcements [sic] access to zero percent the choice for society is clear.

I think this is a major change in government position. Previously, the FBI, the Justice Department and so on had claimed that backdoors for law enforcement could be added without any loss of security. They maintained that technologists just need to figure out how: ­an approach we have derisively named “nerd harder.”

With this change, we can finally have a sensible policy conversation. Yes, adding a backdoor increases our collective security because it allows law enforcement to eavesdrop on the bad guys. But adding that backdoor also decreases our collective security because the bad guys can eavesdrop on everyone. This is exactly the policy debate we should be having­not the fake one about whether or not we can have both security and surveillance.

Barr makes the point that this is about “consumer cybersecurity,” and not “nuclear launch codes.” This is true, but ignores the huge amount of national security-related communications between those two poles. The same consumer communications and computing devices are used by our lawmakers, CEOs, legislators, law enforcement officers, nuclear power plant operators, election officials and so on. There’s no longer a difference between consumer tech and government tech — it’s all the same tech.

Barr also says:

Further, the burden is not as onerous as some make it out to be. I served for many years as the general counsel of a large telecommunications concern. During my tenure, we dealt with these issues and lived through the passage and implementation of CALEA the Communications Assistance for Law Enforcement Act. CALEA imposes a statutory duty on telecommunications carriers to maintain the capability to provide lawful access to communications over their facilities. Companies bear the cost of compliance but have some flexibility in how they achieve it, and the system has by and large worked. I therefore reserve a heavy dose of skepticism for those who claim that maintaining a mechanism for lawful access would impose an unreasonable burden on tech firms especially the big ones. It is absurd to think that we would preserve lawful access by mandating that physical telecommunications facilities be accessible to law enforcement for the purpose of obtaining content, while allowing tech providers to block law enforcement from obtaining that very content.

That telecommunications company was GTE­which became Verizon. Barr conveniently ignores that CALEA-enabled phone switches were used to spy on government officials in Greece in 2003 — which seems to have been an NSA operation — and on a variety of people in Italy in 2006. Moreover, in 2012 every CALEA-enabled switch sold to the Defense Department had security vulnerabilities. (I wrote about all this, and more, in 2013.)

The final thing I noticed about the speech is that is it not about iPhones and data at rest. It is about communications: ­data in transit. The “going dark” debate has bounced back and forth between those two aspects for decades. It seems to be bouncing once again.

I hope that Barr’s latest speech signals that we can finally move on from the fake security vs. privacy debate, and to the real security vs. security debate. I know where I stand on that: As computers continue to permeate every aspect of our lives, society, and critical infrastructure, it is much more important to ensure that they are secure from everybody — even at the cost of law-enforcement access — than it is to allow access at the cost of security. Barr is wrong, it kind of is like these systems are protecting nuclear launch codes.

This essay previously appeared on Lawfare.com.

EDITED TO ADD: More news articles.

EDITED TO ADD (7/28): Gen. Hayden comments.

EDITED TO ADD (7/30): Good response by Robert Graham.

Germany Talking about Banning End-to-End Encryption

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/05/germany_talking.html

Der Spiegel is reporting that the German Ministry for Internal Affairs is planning to require all Internet message services to provide plaintext messages on demand, basically outlawing strong end-to-end encryption. Anyone not complying will be blocked, although the article doesn’t say how. (Cory Doctorow has previously explained why this would be impossible.)

The article is in German, and I would appreciate additional information from those who can speak the language.

EDITED TO ADD (6/2): Slashdot thread. This seems to be nothing more than political grandstanding: see this post from the Carnegie Endowment for International Peace.

Cybersecurity for the Public Interest

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/03/cybersecurity_f_1.html

The Crypto Wars have been waging off-and-on for a quarter-century. On one side is law enforcement, which wants to be able to break encryption, to access devices and communications of terrorists and criminals. On the other are almost every cryptographer and computer security expert, repeatedly explaining that there’s no way to provide this capability without also weakening the security of every user of those devices and communications systems.

It’s an impassioned debate, acrimonious at times, but there are real technologies that can be brought to bear on the problem: key-escrow technologies, code obfuscation technologies, and backdoors with different properties. Pervasive surveillance capitalism — ­as practiced by the Internet companies that are already spying on everyone­ — matters. So does society’s underlying security needs. There is a security benefit to giving access to law enforcement, even though it would inevitably and invariably also give that access to others. However, there is also a security benefit of having these systems protected from all attackers, including law enforcement. These benefits are mutually exclusive. Which is more important, and to what degree?

The problem is that almost no policymakers are discussing this policy issue from a technologically informed perspective, and very few technologists truly understand the policy contours of the debate. The result is both sides consistently talking past each other, and policy proposals — ­that occasionally become law­ — that are technological disasters.

This isn’t sustainable, either for this issue or any of the other policy issues surrounding Internet security. We need policymakers who understand technology, but we also need cybersecurity technologists who understand­ — and are involved in — ­policy. We need public-interest technologists.

Let’s pause at that term. The Ford Foundation defines public-interest technologists as “technology practitioners who focus on social justice, the common good, and/or the public interest.” A group of academics recently wrote that public-interest technologists are people who “study the application of technology expertise to advance the public interest, generate public benefits, or promote the public good.” Tim Berners-Lee has called them “philosophical engineers.” I think of public-interest technologists as people who combine their technological expertise with a public-interest focus: by working on tech policy, by working on a tech project with a public benefit, or by working as a traditional technologist for an organization with a public benefit. Maybe it’s not the best term­ — and I know not everyone likes it­ — but it’s a decent umbrella term that can encompass all these roles.

We need public-interest technologists in policy discussions. We need them on congressional staff, in federal agencies, at non-governmental organizations (NGOs), in academia, inside companies, and as part of the press. In our field, we need them to get involved in not only the Crypto Wars, but everywhere cybersecurity and policy touch each other: the vulnerability equities debate, election security, cryptocurrency policy, Internet of Things safety and security, big data, algorithmic fairness, adversarial machine learning, critical infrastructure, and national security. When you broaden the definition of Internet security, many additional areas fall within the intersection of cybersecurity and policy. Our particular expertise and way of looking at the world is critical for understanding a great many technological issues, such as net neutrality and the regulation of critical infrastructure. I wouldn’t want to formulate public policy about artificial intelligence and robotics without a security technologist involved.

Public-interest technology isn’t new. Many organizations are working in this area, from older organizations like EFF and EPIC to newer ones like Verified Voting and Access Now. Many academic classes and programs combine technology and public policy. My cybersecurity policy class at the Harvard Kennedy School is just one example. Media startups like The Markup are doing technology-driven journalism. There are even programs and initiatives related to public-interest technology inside for-profit corporations.

This might all seem like a lot, but it’s really not. There aren’t enough people doing it, there aren’t enough people who know it needs to be done, and there aren’t enough places to do it. We need to build a world where there is a viable career path for public-interest technologists.

There are many barriers. There’s a report titled A Pivotal Moment that includes this quote: “While we cite individual instances of visionary leadership and successful deployment of technology skill for the public interest, there was a consensus that a stubborn cycle of inadequate supply, misarticulated demand, and an inefficient marketplace stymie progress.”

That quote speaks to the three places for intervention. One: the supply side. There just isn’t enough talent to meet the eventual demand. This is especially acute in cybersecurity, which has a talent problem across the field. Public-interest technologists are a diverse and multidisciplinary group of people. Their backgrounds come from technology, policy, and law. We also need to foster diversity within public-interest technology; the populations using the technology must be represented in the groups that shape the technology. We need a variety of ways for people to engage in this sphere: ways people can do it on the side, for a couple of years between more traditional technology jobs, or as a full-time rewarding career. We need public-interest technology to be part of every core computer-science curriculum, with “clinics” at universities where students can get a taste of public-interest work. We need technology companies to give people sabbaticals to do this work, and then value what they’ve learned and done.

Two: the demand side. This is our biggest problem right now; not enough organizations understand that they need technologists doing public-interest work. We need jobs to be funded across a wide variety of NGOs. We need staff positions throughout the government: executive, legislative, and judiciary branches. President Obama’s US Digital Service should be expanded and replicated; so should Code for America. We need more press organizations that perform this kind of work.

Three: the marketplace. We need job boards, conferences, and skills exchanges­ — places where people on the supply side can learn about the demand.

Major foundations are starting to provide funding in this space: the Ford and MacArthur Foundations in particular, but others as well.

This problem in our field has an interesting parallel with the field of public-interest law. In the 1960s, there was no such thing as public-interest law. The field was deliberately created, funded by organizations like the Ford Foundation. They financed legal aid clinics at universities, so students could learn housing, discrimination, or immigration law. They funded fellowships at organizations like the ACLU and the NAACP. They created a world where public-interest law is valued, where all the partners at major law firms are expected to have done some public-interest work. Today, when the ACLU advertises for a staff attorney, paying one-third to one-tenth normal salary, it gets hundreds of applicants. Today, 20% of Harvard Law School graduates go into public-interest law, and the school has soul-searching seminars because that percentage is so low. Meanwhile, the percentage of computer-science graduates going into public-interest work is basically zero.

This is bigger than computer security. Technology now permeates society in a way it didn’t just a couple of decades ago, and governments move too slowly to take this into account. That means technologists now are relevant to all sorts of areas that they had no traditional connection to: climate change, food safety, future of work, public health, bioengineering.

More generally, technologists need to understand the policy ramifications of their work. There’s a pervasive myth in Silicon Valley that technology is politically neutral. It’s not, and I hope most people reading this today knows that. We built a world where programmers felt they had an inherent right to code the world as they saw fit. We were allowed to do this because, until recently, it didn’t matter. Now, too many issues are being decided in an unregulated capitalist environment where significant social costs are too often not taken into account.

This is where the core issues of society lie. The defining political question of the 20th century was: “What should be governed by the state, and what should be governed by the market?” This defined the difference between East and West, and the difference between political parties within countries. The defining political question of the first half of the 21st century is: “How much of our lives should be governed by technology, and under what terms?” In the last century, economists drove public policy. In this century, it will be technologists.

The future is coming faster than our current set of policy tools can deal with. The only way to fix this is to develop a new set of policy tools with the help of technologists. We need to be in all aspects of public-interest work, from informing policy to creating tools all building the future. The world needs all of our help.

This essay previously appeared in the January/February issue of IEEE Security & Privacy.

Together with the Ford Foundation, I am hosting a one-day mini-track on public-interest technologists at the RSA Conference this week on Thursday. We’ve had some press coverage.

Edited to Add (3/7): More news articles.

Hacking the GCHQ Backdoor

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/01/hacking_the_gch.html

Last week, I evaluated the security of a recent GCHQ backdoor proposal for communications systems. Furthering the debate, Nate Cardozo and Seth Schoen of EFF explain how this sort of backdoor can be detected:

In fact, we think when the ghost feature is active­ — silently inserting a secret eavesdropping member into an otherwise end-to-end encrypted conversation in the manner described by the GCHQ authors­ — it could be detected (by the target as well as certain third parties) with at least four different techniques: binary reverse engineering, cryptographic side channels, network-traffic analysis, and crash log analysis. Further, crash log analysis could lead unrelated third parties to find evidence of the ghost in use, and it’s even possible that binary reverse engineering could lead researchers to find ways to disable the ghost capability on the client side. It should be obvious that none of these possibilities are desirable for law enforcement or society as a whole. And while we’ve theorized some types of mitigations that might make the ghost less detectable by particular techniques, they could also impose considerable costs to the network when deployed at the necessary scale, as well as creating new potential security risks or detection methods.

Other critiques of the system were written by Susan Landau and Matthew Green.

EDITED TO ADD (1/26): Good commentary on how to defeat the backdoor detection.

Evaluating the GCHQ Exceptional Access Proposal

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2019/01/evaluating_the_.html

The so-called Crypto Wars have been going on for 25 years now. Basically, the FBI — and some of their peer agencies in the UK, Australia, and elsewhere — argue that the pervasive use of civilian encryption is hampering their ability to solve crimes and that they need the tech companies to make their systems susceptible to government eavesdropping. Sometimes their complaint is about communications systems, like voice or messaging apps. Sometimes it’s about end-user devices. On the other side of this debate is pretty much all technologists working in computer security and cryptography, who argue that adding eavesdropping features fundamentally makes those systems less secure.

A recent entry in this debate is a proposal by Ian Levy and Crispin Robinson, both from the UK’s GCHQ (the British signals-intelligence agency — basically, its NSA). It’s actually a positive contribution to the discourse around backdoors; most of the time government officials broadly demand that the tech companies figure out a way to meet their requirements, without providing any details. Levy and Robinson write:

In a world of encrypted services, a potential solution could be to go back a few decades. It’s relatively easy for a service provider to silently add a law enforcement participant to a group chat or call. The service provider usually controls the identity system and so really decides who’s who and which devices are involved — they’re usually involved in introducing the parties to a chat or call. You end up with everything still being end-to-end encrypted, but there’s an extra ‘end’ on this particular communication. This sort of solution seems to be no more intrusive than the virtual crocodile clips that our democratically elected representatives and judiciary authorise today in traditional voice intercept solutions and certainly doesn’t give any government power they shouldn’t have.

On the surface, this isn’t a big ask. It doesn’t affect the encryption that protects the communications. It only affects the authentication that assures people of whom they are talking to. But it’s no less dangerous a backdoor than any others that have been proposed: It exploits a security vulnerability rather than fixing it, and it opens all users of the system to exploitation of that same vulnerability by others.

In a blog post, cryptographer Matthew Green summarized the technical problems with this GCHQ proposal. Basically, making this backdoor work requires not only changing the cloud computers that oversee communications, but it also means changing the client program on everyone’s phone and computer. And that change makes all of those systems less secure. Levy and Robinson make a big deal of the fact that their backdoor would only be targeted against specific individuals and their communications, but it’s still a general backdoor that could be used against anybody.

The basic problem is that a backdoor is a technical capability — a vulnerability — that is available to anyone who knows about it and has access to it. Surrounding that vulnerability is a procedural system that tries to limit access to that capability. Computers, especially internet-connected computers, are inherently hackable, limiting the effectiveness of any procedures. The best defense is to not have the vulnerability at all.

That old physical eavesdropping system Levy and Robinson allude to also exploits a security vulnerability. Because telephone conversations were unencrypted as they passed through the physical wires of the phone system, the police were able to go to a switch in a phone company facility or a junction box on the street and manually attach alligator clips to a specific pair and listen in to what that phone transmitted and received. It was a vulnerability that anyone could exploit — not just the police — but was mitigated by the fact that the phone company was a monolithic monopoly, and physical access to the wires was either difficult (inside a phone company building) or obvious (on the street at a junction box).

The functional equivalent of physical eavesdropping for modern computer phone switches is a requirement of a 1994 U.S. law called CALEA — and similar laws in other countries. By law, telephone companies must engineer phone switches that the government can eavesdrop, mirroring that old physical system with computers. It is not the same thing, though. It doesn’t have those same physical limitations that make it more secure. It can be administered remotely. And it’s implemented by a computer, which makes it vulnerable to the same hacking that every other computer is vulnerable to.

This isn’t a theoretical problem; these systems have been subverted. The most public incident dates from 2004 in Greece. Vodafone Greece had phone switches with the eavesdropping feature mandated by CALEA. It was turned off by default in the Greek phone system, but the NSA managed to surreptitiously turn it on and use it to eavesdrop on the Greek prime minister and over 100 other high-ranking dignitaries.

There’s nothing distinct about a phone switch that makes it any different from other modern encrypted voice or chat systems; any remotely administered backdoor system will be just as vulnerable. Imagine a chat program added this GCHQ backdoor. It would have to add a feature that added additional parties to a chat from somewhere in the system — and not by the people at the endpoints. It would have to suppress any messages alerting users to another party being added to that chat. Since some chat programs, like iMessage and Signal, automatically send such messages, it would force those systems to lie to their users. Other systems would simply never implement the “tell me who is in this chat conversation” feature­which amounts to the same thing.

And once that’s in place, every government will try to hack it for its own purposes­ — just as the NSA hacked Vodafone Greece. Again, this is nothing new. In 2010, China successfully hacked the back-door mechanism Google put in place to meet law-enforcement requests. In 2015, someone — we don’t know who — hacked an NSA backdoor in a random-number generator used to create encryption keys, changing the parameters so they could also eavesdrop on the communications. There are certainly other stories that haven’t been made public.

Simply adding the feature erodes public trust. If you were a dissident in a totalitarian country trying to communicate securely, would you want to use a voice or messaging system that is known to have this sort of backdoor? Who would you bet on, especially when the cost of losing the bet might be imprisonment or worse: the company that runs the system, or your country’s government intelligence agency? If you were a senior government official, or the head of a large multinational corporation, or the security manager or a critical technician at a power plant, would you want to use this system?

Of course not.

Two years ago, there was a rumor of a WhatsApp backdoor. The details are complicated, and calling it a backdoor or a vulnerability is largely inaccurate — but the resultant confusion caused some people to abandon the encrypted messaging service.

Trust is fragile, and transparency is essential to trust. And while Levy and Robinson state that “any exceptional access solution should not fundamentally change the trust relationship between a service provider and its users,” this proposal does exactly that. Communications companies could no longer be honest about what their systems were doing, and we would have no reason to trust them if they tried.

In the end, all of these exceptional access mechanisms, whether they exploit existing vulnerabilities that should be closed or force vendors to open new ones, reduce the security of the underlying system. They reduce our reliance on security technologies we know how to do well — cryptography — to computer security technologies we are much less good at. Even worse, they replace technical security measures with organizational procedures. Whether it’s a database of master keys that could decrypt an iPhone or a communications switch that orchestrates who is securely chatting with whom, it is vulnerable to attack. And it will be attacked.

The foregoing discussion is a specific example of a broader discussion that we need to have, and it’s about the attack/defense balance. Which should we prioritize? Should we design our systems to be open to attack, in which case they can be exploited by law enforcement — and others? Or should we design our systems to be as secure as possible, which means they will be better protected from hackers, criminals, foreign governments and — unavoidably — law enforcement as well?

This discussion is larger than the FBI’s ability to solve crimes or the NSA’s ability to spy. We know that foreign intelligence services are targeting the communications of our elected officials, our power infrastructure, and our voting systems. Do we really want some foreign country penetrating our lawful-access backdoor in the same way the NSA penetrated Greece’s?

I have long maintained that we need to adopt a defense-dominant strategy: We should prioritize our need for security over our need for surveillance. This is especially true in the new world of physically capable computers. Yes, it will mean that law enforcement will have a harder time eavesdropping on communications and unlocking computing devices. But law enforcement has other forensic techniques to collect surveillance data in our highly networked world. We’d be much better off increasing law enforcement’s technical ability to investigate crimes in the modern digital world than we would be to weaken security for everyone. The ability to surreptitiously add ghost users to a conversation is a vulnerability, and it’s one that we would be better served by closing than exploiting.

This essay originally appeared on Lawfare.com.

EDITED TO ADD (1/30): More commentary.

New Australian Backdoor Law

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/12/new_australian_.html

Last week, Australia passed a law giving the government the ability to demand backdoors in computers and communications systems. Details are still to be defined, but it’s really bad.

Note: Many people e-mailed me to ask why I haven’t blogged this yet. One, I was busy with other things. And two, there’s nothing I can say that I haven’t said many times before.

If there are more good links or commentary, please post them in the comments.

EDITED TO ADD (12/13): The Australian government response is kind of embarrassing.

More on the Five Eyes Statement on Encryption and Backdoors

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/10/more_on_the_fiv.html

Earlier this month, I wrote about a statement by the Five Eyes countries about encryption and back doors. (Short summary: they like them.) One of the weird things about the statement is that it was clearly written from a law-enforcement perspective, though we normally think of the Five Eyes as a consortium of intelligence agencies.

Susan Landau examines the details of the statement, explains what’s going on, and why the statement is a lot less than what it might seem.

Ray Ozzie’s Encryption Backdoor

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/05/ray_ozzies_encr.html

Last month, Wired published a long article about Ray Ozzie and his supposed new scheme for adding a backdoor in encrypted devices. It’s a weird article. It paints Ozzie’s proposal as something that “attains the impossible” and “satisfies both law enforcement and privacy purists,” when (1) it’s barely a proposal, and (2) it’s essentially the same key escrow scheme we’ve been hearing about for decades.

Basically, each device has a unique public/private key pair and a secure processor. The public key goes into the processor and the device, and is used to encrypt whatever user key encrypts the data. The private key is stored in a secure database, available to law enforcement on demand. The only other trick is that for law enforcement to use that key, they have to put the device in some sort of irreversible recovery mode, which means it can never be used again. That’s basically it.

I have no idea why anyone is talking as if this were anything new. Several cryptographers have already explained why this key escrow scheme is no better than any other key escrow scheme. The short answer is (1) we won’t be able to secure that database of backdoor keys, (2) we don’t know how to build the secure coprocessor the scheme requires, and (3) it solves none of the policy problems around the whole system. This is the typical mistake non-cryptographers make when they approach this problem: they think that the hard part is the cryptography to create the backdoor. That’s actually the easy part. The hard part is ensuring that it’s only used by the good guys, and there’s nothing in Ozzie’s proposal that addresses any of that.

I worry that this kind of thing is damaging in the long run. There should be some rule that any backdoor or key escrow proposal be a fully specified proposal, not just some cryptography and hand-waving notions about how it will be used in practice. And before it is analyzed and debated, it should have to satisfy some sort of basic security analysis. Otherwise, we’ll be swatting pseudo-proposals like this one, while those on the other side of this debate become increasingly convinced that it’s possible to design one of these things securely.

Already people are using the National Academies report on backdoors for law enforcement as evidence that engineers are developing workable and secure backdoors. Writing in Lawfare, Alan Z. Rozenshtein claims that the report — and a related New York Times story — “undermine the argument that secure third-party access systems are so implausible that it’s not even worth trying to develop them.” Susan Landau effectively corrects this misconception, but the damage is done.

Here’s the thing: it’s not hard to design and build a backdoor. What’s hard is building the systems — both technical and procedural — around them. Here’s Rob Graham:

He’s only solving the part we already know how to solve. He’s deliberately ignoring the stuff we don’t know how to solve. We know how to make backdoors, we just don’t know how to secure them.

A bunch of us cryptographers have already explained why we don’t think this sort of thing will work in the foreseeable future. We write:

Exceptional access would force Internet system developers to reverse “forward secrecy” design practices that seek to minimize the impact on user privacy when systems are breached. The complexity of today’s Internet environment, with millions of apps and globally connected services, means that new law enforcement requirements are likely to introduce unanticipated, hard to detect security flaws. Beyond these and other technical vulnerabilities, the prospect of globally deployed exceptional access systems raises difficult problems about how such an environment would be governed and how to ensure that such systems would respect human rights and the rule of law.

Finally, Matthew Green:

The reason so few of us are willing to bet on massive-scale key escrow systems is that we’ve thought about it and we don’t think it will work. We’ve looked at the threat model, the usage model, and the quality of hardware and software that exists today. Our informed opinion is that there’s no detection system for key theft, there’s no renewability system, HSMs are terrifically vulnerable (and the companies largely staffed with ex-intelligence employees), and insiders can be suborned. We’re not going to put the data of a few billion people on the line an environment where we believe with high probability that the system will fail.

EDITED TO ADD (5/14): An analysis of the proposal.

Two New Papers on the Encryption Debate

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/03/two_new_papers_.html

Seems like everyone is writing about encryption and backdoors this season.

I recently blogged about the new National Academies report on the same topic.

Here’s a review of the National Academies report, and another of the East West Institute’s report.

EDITED TO ADD (3/8): Commentary on the National Academies study by the EFF.

Yet Another FBI Proposal for Insecure Communications

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/01/yet_another_fbi.html

Deputy Attorney General Rosenstein has given talks where he proposes that tech companies decrease their communications and device security for the benefit of the FBI. In a recent talk, his idea is that tech companies just save a copy of the plaintext:

Law enforcement can also partner with private industry to address a problem we call “Going Dark.” Technology increasingly frustrates traditional law enforcement efforts to collect evidence needed to protect public safety and solve crime. For example, many instant-messaging services now encrypt messages by default. The prevent the police from reading those messages, even if an impartial judge approves their interception.

The problem is especially critical because electronic evidence is necessary for both the investigation of a cyber incident and the prosecution of the perpetrator. If we cannot access data even with lawful process, we are unable to do our job. Our ability to secure systems and prosecute criminals depends on our ability to gather evidence.

I encourage you to carefully consider your company’s interests and how you can work cooperatively with us. Although encryption can help secure your data, it may also prevent law enforcement agencies from protecting your data.

Encryption serves a valuable purpose. It is a foundational element of data security and essential to safeguarding data against cyber-attacks. It is critical to the growth and flourishing of the digital economy, and we support it. I support strong and responsible encryption.

I simply maintain that companies should retain the capability to provide the government unencrypted copies of communications and data stored on devices, when a court orders them to do so.

Responsible encryption is effective secure encryption, coupled with access capabilities. We know encryption can include safeguards. For example, there are systems that include central management of security keys and operating system updates; scanning of content, like your e-mails, for advertising purposes; simulcast of messages to multiple destinations at once; and key recovery when a user forgets the password to decrypt a laptop. No one calls any of those functions a “backdoor.” In fact, those very capabilities are marketed and sought out.

I do not believe that the government should mandate a specific means of ensuring access. The government does not need to micromanage the engineering.

The question is whether to require a particular goal: When a court issues a search warrant or wiretap order to collect evidence of crime, the company should be able to help. The government does not need to hold the key.

Rosenstein is right that many services like Gmail naturally keep plaintext in the cloud. This is something we pointed out in our 2016 paper: “Don’t Panic.” But forcing companies to build an alternate means to access the plaintext that the user can’t control is an enormous vulnerability.

FBI Increases Its Anti-Encryption Rhetoric

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/10/fbi_increases_i.html

Earlier this month, Deputy Attorney General Rod Rosenstein gave a speech warning that a world with encryption is a world without law — or something like that. The EFF’s Kurt Opsahl takes it apart pretty thoroughly.

Last week, FBI Director Christopher Wray said much the same thing.

This is an idea that will not die.

Australia Considering New Law Weakening Encryption

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/07/australia_consi.html

News from Australia:

Under the law, internet companies would have the same obligations telephone companies do to help law enforcement agencies, Prime Minister Malcolm Turnbull said. Law enforcement agencies would need warrants to access the communications.

“We’ve got a real problem in that the law enforcement agencies are increasingly unable to find out what terrorists and drug traffickers and pedophile rings are up to because of the very high levels of encryption,” Turnbull told reporters.

“Where we can compel it, we will, but we will need the cooperation from the tech companies,” he added.

Never mind that the law 1) would not achieve the desired results because all the smart “terrorists and drug traffickers and pedophile rings” will simply use a third-party encryption app, and 2) would make everyone else in Australia less secure. But that’s all ground I’ve covered before.

I found this bit amusing:

Asked whether the laws of mathematics behind encryption would trump any new legislation, Mr Turnbull said: “The laws of Australia prevail in Australia, I can assure you of that.

“The laws of mathematics are very commendable but the only law that applies in Australia is the law of Australia.”

Next Turnbull is going to try to legislate that pi = 3.2.

Another article. BoingBoing post.

EDITED TO ADD: More commentary.

The US Senate Is Using Signal

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/05/the_us_senate_i.html

The US Senate just approved Signal for staff use. Signal is a secure messaging app with no backdoor, and no large corporate owner who can be pressured to install a backdoor.

Susan Landau comments.

Maybe I’m being optimistic, but I think we just won the Crypto War. A very important part of the US government is prioritizing security over surveillance.

Encryption Policy and Freedom of the Press

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/04/encryption_poli.html

Interesting law journal article: “Encryption and the Press Clause,” by D. Victoria Barantetsky.

Abstract: Almost twenty years ago, a hostile debate over whether government could regulate encryption — later named the Crypto Wars — seized the country. At the center of this debate stirred one simple question: is encryption protected speech? This issue touched all branches of government percolating from Congress, to the President, and eventually to the federal courts. In a waterfall of cases, several United States Court of Appeals appeared to reach a consensus that encryption was protected speech under the First Amendment, and with that the Crypto Wars appeared to be over, until now.

Nearly twenty years later, the Crypto Wars have returned. Following recent mass shootings, law enforcement has once again questioned the legal protection for encryption and tried to implement “backdoor” techniques to access messages sent over encrypted channels. In the case, Apple v. FBI, the agency tried to compel Apple to grant access to the iPhone of a San Bernardino shooter. The case was never decided, but the legal arguments briefed before the court were essentially the same as they were two decades prior. Apple and amici supporting the company argued that encryption was protected speech.

While these arguments remain convincing, circumstances have changed in ways that should be reflected in the legal doctrines that lawyers use. Unlike twenty years ago, today surveillance is ubiquitous, and the need for encryption is no longer felt by a seldom few. Encryption has become necessary for even the most basic exchange of information given that most Americans share “nearly every aspect of their lives ­– from the mundane to the intimate” over the Internet, as stated in a recent Supreme Court opinion.

Given these developments, lawyers might consider a new justification under the Press Clause. In addition to the many doctrinal concerns that exist with protection under the Speech Clause, the
Press Clause is normatively and descriptively more accurate at protecting encryption as a tool for secure communication without fear of government surveillance. This Article outlines that framework by examining the historical and theoretical transformation of the Press Clause since its inception.

More on the Going Dark Debate

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2016/05/more_on_the_goi.html

Lawfare is turning out to be the go-to blog for policy wonks about various government debates on cybersecurity. There are two good posts this week on the Going Dark debate.

The first is from those of us who wrote the “Keys Under Doormats” paper last year, criticizing the concept of backdoors and key escrow. We were responding to a half-baked proposal on how to give the government access without causing widespread insecurity, and we pointed out where almost of all of these sorts of proposals fall short:

1. Watch for systems that rely on a single powerful key or a small set of them.

2. Watch for systems using high-value keys over and over and still claiming not to increase risk.

3. Watch for the claim that the abstract algorithm alone is the measure of system security.

4. Watch for the assumption that scaling anything on the global Internet is easy.

5. Watch for the assumption that national borders are not a factor.

6. Watch for the assumption that human rights and the rule of law prevail throughout the world.

The second is by Susan Landau, and is a response to the ODNI’s response to the “Don’t Panic” report. Our original report said basically that the FBI wasn’t going dark and that surveillance information is everywhere. At a Senate hearing, Sen. Wyden requested that the Office of the Director of National Intelligence respond to the report. It did — not very well, honestly — and Landau responded to that response. She pointed out that there really wasn’t much disagreement: that the points it claimed to have issue with were actually points we made and agreed with.

In the end, the ODNI’s response to our report leaves me somewhat confused. The reality is that the only strong disagreement seems to be with an exaggerated view of one finding. It almost appears as if ODNI is using the Harvard report as an opportunity to say, “Widespread use of encryption will make our work life more difficult.” Of course it will. Widespread use of encryption will also help prevent some of the cybersecurity exploits and attacks we have been experiencing over the last decade. The ODNI letter ignored that issue.