In Memoriam: Frederick P. Brooks, Jr. – a Personal Recollection

Brooks is famous for many things. Many people know him best as the author of The Mythical Man-Month, his musings on software engineering and why it's so very hard. Some of his prescriptions seem quaint today -- no one these days would print out documentation on microfiche every night to distribute to developers -- but his observations about the problems of development remain spot-on. But he did so much more. more

The Importance of Understanding Attacker Target Selection

There's a bit of a debate going on about whether the Kaseya attack exploited a 0-day vulnerability. While that's an interesting question when discussing, say, patch management strategies, I think it's less important to understand attackers' thinking than understand their target selection. In a nutshell, the attackers have outmaneuvered defenders for almost 30 years when it comes to target selection. more

Where Did “Data Shadow” Come From?

Anyone who works in privacy is familiar with the term "data shadow": the digital record created by our transactions, our travels, our online activities. But where did the phrase come from? Who used it first? A number of authors have attributed it to Alan Westin, whose seminal book Privacy and Freedom (largely a report on the work of the Committee on Science and Law of the Association of the Bar of the City of New York) set the stage for most modern discussions of privacy.  more

An Inquiry Into an Organization’s Security Priorities

In the wake of recent high-profile security incidents, I started wondering: what, generally speaking, should an organization's security priorities be? That is, given a finite budget - and everyone's budget is finite - what should you do first? More precisely, what security practices or features will give you the most protection per zorkmid? I suggested two of my own, and then asked my infosec-heavy Twitter feed for suggestions. more

Hot Take on the Twitter Hack

If you read this blog, you've probably heard by now about the massive Twitter hack. Briefly, many high-profile accounts were taken over and used to tweet scam requests to send Bitcoins to a particular wallet, with the promise of double your money back. Because some of the parties hit are sophisticated and security-aware, it seems unlikely that the attack was a straightforward one directly on these accounts. more

Trust Binding

A few months ago, there was a lot of discussion that despite its claims, Zoom did not actually offer end-to-end encryption. They're in the process of fixing that, which is good, but that raises a deeper question: why trust their code? (To get ahead of myself, this blog post is not about Zoom.) If Zoom has the key but doesn't abuse it, there isn't a problem, right? Let's fast-forward to when they deploy true end-to-end encryption. Why do we trust their code not to leak the secret key? more

The Price of Lack of Clarity

As anyone reading this blog, assuredly knows, the world is in the grip of a deadly pandemic. One way to contain it is contact-tracing: finding those who have been near infected people and getting them to self-quarantine. Some experts think that because of how rapidly newly infected individuals themselves become contagious, we need some sort of automated scheme. That is, traditional contact tracing is labor-intensive and time-consuming - a time we don't have. more

Is Zoom’s Server Security Just as Vulnerable as the Client Side?

Zoom programmers made elementary security errors when coding, and did not use protective measures that compiler toolchains make available. It's not a great stretch to assume that similar flaws afflict their server implementations. While Mudge noted that Zoom's Windows and Mac clients are (possibly accidentally) somewhat safer than the Linux client, I suspect that their servers run on Linux.Were they written with similar lack of attention to security? more

Trusting Zoom?

Since the world went virtual, often by using Zoom, several people have asked me if I use it, and if so, do I use their app or their web interface. If I do use it, isn't this odd, given that I've been doing security and privacy work for more than 30 years, and "everyone" knows that Zoom is a security disaster? To give too short an answer to a very complicated question: I do use it, via both Mac and iOS apps. Some of my reasons are specific to me and may not apply to you... more

Zoom Cryptography and Authentication Problems

In my last blog post about Zoom, I noted that the company says "that critics have misunderstood how they do encryption." New research from Citizen Lab show that not only were the critics correct, Zoom's design shows that they're completely ignorant about encryption. When companies roll their own crypto, I expect it to have flaws. I don't expect those flaws to be errors I'd find unacceptable in an introductory undergraduate class, but that's what happened here. more

Zoom Security: The Good, the Bad, and the Business Model

Zoom - one of the hottest companies on the planet right now, as businesses, schools, and individuals switch to various forms of teleconferencing due to the pandemic - has come in for much criticism due to assorted security and privacy flaws. Some of the problems are real but easily fixable, some are due to a mismatch between what Zoom was intended for and how it's being used now - and some are worrisome. more

Y2038: It’s a Threat

Last month, for the 20th anniversary of Y2K, I was asked about my experiences. (Short answer: there really was a serious potential problem, but disaster was averted by a lot of hard work by a lot of unsung programmers.) I joked that, per this T-shirt I got from a friend, the real problem would be on January 19, 2038, and 03:14:08 GMT. Why might that date be such a problem? On Unix-derived systems, including Linux and MacOS, time is stored internally as the number of seconds since... more

The Early History of Usenet, Part IX: Retrospective Thoughts

Usenet is 40 years old. Did we get it right, way back when? What could/should we have done differently, with the technology of the time and with what we should have known or could feasibly have learned? And what are the lessons for today? A few things were obviously right, even in retrospect. For the expected volume of communications and expected connectivity, a flooding algorithm was the only real choice. more

The Early History of Usenet, Part VIII: The Great Renaming

The Great Renaming was a significant event in Usenet history since it involved issues of technology, money, and governance. From a personal perspective -- and remember that this series of blog posts is purely my recollections – it also marked the end of my "official" involvement in "running" Usenet. I put "running" in quotation marks in the previous sentence because of the difficulty of actually controlling a non-hierarchical, distributed system with no built-in, authenticated control mechanisms. more

The Early History of Usenet, Part VII: Usenet Growth and B-News

For quite a while, it looked like my prediction – one to two articles per day – was overly optimistic. By summer, there were only four new sites: Reed College, University of Oklahoma (at least, I think that that's what uucp node uok is), vax135, another Bell Labs machine – and, cruciallyy, U.C. Berkeley, which had a uucp connection to Bell Labs Research and was on the ARPANET. more

The Early History of Usenet, Part VI: The Public Announcement

Our goal was to announce Usenet at the January, 1980 Usenix meeting. In those days, Usenix met at universities; it was a small, comaparatively informal organization, and didn't require hotel meeting rooms and the like. (I don't know just when Usenix started being a formal academic-style conference; I do know that it was no later than 1984, since I was on the program committee that year for what would later be called the Annual Technical Conference.) more

The Early History of Usenet, Part V: Authentication and Norms

We knew that Usenet needed some sort of management system, and we knew that that would require some sort of authentication, for users, sites, and perhaps posts. We didn't add any, though -- and why we didn't is an interesting story. The obvious solution was something involving public key cryptography, which we (the original developers of the protocol: Tom Truscott, the late Jim Ellis, and myself) knew about: all good geeks at the time had seen Martin Gardner's "Mathematical Games" column... more

The Early History of Usenet, Part IV: Implementation and User Experience

To understand some of our implementation choices, it's important to remember two things. First, the computers of that era were slow. The Unix machine at UNC's CS department was slower than most timesharing machines even for 1979 – we had a small, slow disk, a slow CPU, and – most critically – not nearly enough RAM. Duke CS had a faster computer – they had an 11/70; we had an 11/45 -- but since I was doing the first implementation, I had to use what UNC had. (Log in remotely? more

The Early History of Usenet, Part III: File Format

When we set out to design the over-the-wire file format, we were certain of one thing: we wouldn't get it perfectly right. That led to our first decision: the very first character of the transmitted file would be the letter "A" for the version. Why not a number on the first line, including perhaps a decimal point? If we ever considered that, I have no recollection of it. more

The Early History of Usenet, Part II: Hardware and Economics

There was a planning meeting for what became Usenet at Duke CS. We knew three things, and three things only: we wanted something that could be used locally for administrative messages, we wanted a networked system, and we would use uucp for intersite communication. This last decision was more or less by default: there were no other possibilities available to us or to most other sites that ran standard Unix. Furthermore, all you needed to run uucp was a single dial-up modem port. more

The Early History of Usenet, Part I: The Technological Setting

Usenet -- Netnews -- was conceived almost exactly 40 years ago this month. To understand where it came from and why certain decisions were made the way they were, it's important to understand the technological constraints of the time. Metanote: this is a personal history as I remember it. None of us were taking notes at the time; it's entirely possible that errors have crept in, especially since my brain cells do not even have parity checking, let alone ECC. Please send any corrections. more

The Crypto Wars Resume

For decades, the US government has fought against widespread, strong encryption. For about as long, privacy advocates and technologists have fought for widespread, strong encryption, to protect not just privacy but also as a tool to secure our computers and our data. The government has proposed a variety of access mechanisms and mandates to permit them to decrypt (lawfully) obtained content; technologists have asserted that "back doors" are inherently insecure. more

What is a Security Mechanism?

Orin Kerr recently blogged about a 9th Circuit decision that held that scraping a public web site (probably) doesn't violate the Computer Fraud and Abuse Act (CFAA)... On its surface, it makes sense – you can't steal something that's public – but I think the simplicity of the rule is hiding some profound questions. One, I believe, can most easily be expressed as "what is the cost of the 'attack'"? That is, how much effort must someone expend to get the data? Does that matter? Should it? more

Facebook, Privacy, and Cryptography

There has long been pressure from governments to provide back doors in encryption systems. Of course, if the endpoints are insecure it doesn't matter much if the transmission is encrypted; indeed, a few years ago, I and some colleagues even suggested lawful hacking as an alternative. Crucially, we said that this should be done by taking advantage of existing security holes rather than be creating new ones. more

A Dangerous, Norm-Destroying Attack

Kim Zetter has a new story out describing a very serious attack. In fact, the implications are about as bad as possible. The attack has been dubbed ShadowHammer by Kaspersky Lab, which discovered it. Briefly, some crew of attackers -- I suspect an intelligence agency; more on that below -- has managed to abuse ASUS' update channel and private signing key to distribute bogus patches. more

Facebook and Privacy

Mark Zuckerberg shocked a lot of people by promising a new focus on privacy for Facebook. There are many skeptics; Zuckerberg himself noted that the company doesn't "currently have a strong reputation for building privacy protective services." And there are issues that his blog post doesn't address; Zeynep Tufekci discusses many of them While I share many of her concerns, I think there are some other issues - and risks. more

Microsoft is Abandoning SHA-1 Hashes for Updates - But Why?

Microsoft is shipping a patch to eliminate SHA-1 hashes from its update process. There's nothing wrong with eliminating SHA-1 - but their reasoning may be very interesting. SHA-1 is a "cryptographic hash function". That is, it takes an input file of any size and outputs 20 bytes. An essential property of cryptographic hash functions is that in practice (though obviously not in theory), no two files should have the same hash value unless the files are identical. more

Protecting Privacy Differently

My thesis is simple: the way we protect privacy today is broken and cannot be fixed without a radical change in direction. My full argument is long; I submitted it to the NTIA's request for comments on privacy. Here's a short summary. For almost 50 years, privacy protection has been based on the Fair Information Practice Principles (FIPPs). There are several provisions... more

Why Foldering Adds Very Little Security

I keep hearing stories of people using "foldering" for covert communications. Foldering is the process of composing a message for another party, but instead of sending it as an email, you leave it in the Drafts folder. The other party then logs in to the same email account and reads the message; they can then reply via the same technique. Foldering has been used for a long time, most famously by then-CIA director David Petraeus and his biographer/lover Paula Broadwell. Why is foldering used? more

The Economics of Hacking an Election

There have been many news stories of late about potential attacks on the American electoral system. Which attacks are actually serious? As always, the answer depends on economics. There are two assertions I'll make up front. First, the attacker -- any attacker -- is resource-limited. They may have vast resources, and in particular, they may have more resources than the defenders -- but they're still limited. Why? more

Why Government Agencies Use Ugly, Difficult to Use Scanned PDFs - There’s More Than Meets the Eye

Sometimes, a government agency will post a PDF that doesn't contain searchable text. Most often, it's a scan of a printout. Why? Don't the NSA, the Department of Justice, etc., know how to convert Word (or whatever) directly to PDF? It turns out that they know more than some of their critics do. The reason? With a piece of paper, you know much more about what you're actually disclosing. more

The Security Problem with HTML Email

Purists have long objected to HTML email on aesthetic grounds. On functional grounds, it tempts too many sites to put essential content in embedded (or worse yet, remote) images, thus making the messages not findable via search. For these reasons, among others, Matt Blaze remarked that "I've long thought HTML email is the work of the devil". But there are inherent security problems, too (and that, of course, is some of what Matt was referring to). Why? more

Crypto War III: Assurance

For decades, academics and technologists have sparred with the government over access to crypographic technology. In the 1970s, when crypto started to become an academic discipline, the NSA was worried, fearing that they'd lose the ability to read other countries' traffic. And they acted. For example, they exerted pressure to weaken DES... The Second Crypto War, in the 1990s, is better known today, with the battles over the Clipper Chip, export rules, etc. more

Usenet, Authentication, and Engineering (or: Early Design Decisions for Usenet)

A Twitter thread on trolls brought up mention of trolls on Usenet. The reason they were so hard to deal with, even then, has some lessons for today; besides, the history is interesting. (Aside: this is, I think, the first longish thing I've ever written about any of the early design decisions for Usenet. I should note that this is entirely my writing, and memory can play many tricks across nearly 40 years.) more

Meltdown and Spectre: Security is a Systems Property

I don't (and probably won't) have anything substantive to say about the technical details of the just-announced Meltdown and Spectre attacks. What I do want to stress is that these show, yet again, that security is a systems property: being secure requires that every component, including ones you've never heard of, be secure. These attacks depend on hardware features... and no, many computer programmers don't know what those are, either. more

Bitcoin: The Andromeda Strain of Computer Science Research

Everyone knows about Bitcoin. Opinions are divided: it's either a huge bubble, best suited for buying tulip bulbs, or, as one Twitter rather hyperbolically expressed it, "the most important application of cryptography in human history". I personally am in the bubble camp, but I think there's another lesson here, on the difference between science and engineering. Bitcoin and the blockchain are interesting ideas that escaped the laboratory without proper engineering - and it shows. Let's start with the upside. more

Voluntary Reporting of Cybersecurity Incidents

One of the problems with trying to secure systems is the lack of knowledge in the community about what has or hasn't worked. I'm on record as calling for an analog to the National Transportation Safety Board: a government agency that investigates major outages and publishes the results. In the current, deregulatory political climate, though, that isn't going to happen. But how about a voluntary system? more

Two More Crypto Holes

If you work in computer security, your Twitter feed and/or Inbox has just exploded with stories about not just one but two new holes in cryptographic protcols. One affects WiFi; the other affects RSA key pair generation by certain chips. How serious are these? I'm not going to go through the technical details. For KRACK, Matthew Green did an excellent blog post; for the other, full details are not yet available. There are also good articles on each of them. What's more interesting are the implications. more

Preliminary Thoughts on the Equifax Hack

As you've undoubtedly heard, the Equifax credit reporting agency was hit by a major attack, exposing the personal data of 143 million Americans and many more people in other countries. There's been a lot of discussion of liability; as of a few days ago, at least 25 lawsuits had been filed, with the state of Massachusetts preparing its own suit. It's certainly too soon to draw any firm conclusions... but there are a number of interesting things we can glean from Equifax's latest statement. more

Security is a System Property

There's lots of security advice in the press: keep your systems patched, use a password manager, don't click on links in email, etc. But there's one thing these adages omit: an attacker who is targeting you, rather than whoever falls for the phishing email, won't be stopped by one defensive measure. Rather, they'll go after the weakest part of your defenses. You have to protect everything -- including things you hadn't realized were relevant. more

Security Costs Money. So - Who Pays?

Computer security costs money. It costs more to develop secure software, and there's an ongoing maintenance cost to patch the remaining holes. Spending more time and money up front will likely result in lesser maintenance costs going forward, but too few companies do that. Besides, even very secure operating systems like Windows 10 and iOS have had security problems and hence require patching. (I just installed iOS 10.3.2 on my phone. It fixed about two dozen security holes.) more

Patching is Hard

There are many news reports of a ransomware worm. Much of the National Health Service in the UK has been hit; so has FedEx. The patch for the flaw exploited by this malware has been out for a while, but many companies haven't installed it. Naturally, this has prompted a lot of victim-blaming: they should have patched their systems. Yes, they should have, but many didn't. Why not? Because patching is very hard and very risk, and the more complex your systems are, the harder and riskier it is. more

Wikileaks, the CIA, and the Press

As you've probably read, WikiLeaks has released a trove of purported CIA documents describing their hacking tools. There's a lot more that will be learned, as people work their way through the documents. For now, though, I want to focus on something that's being misreported, possibly because of deliberately misleading text by WikiLeaks itself. Here's the text from WikiLeaks... more

Does Apple’s Cloud Key Vault Answer the Key Escrow Question?

In a recent talk at Black Hat, Apple's head of security engineering (Ivan Krsti?) described many security mechanisms in iOS. One in particular stood out: Apple's Cloud Key Vault, the way that Apple protects cryptographic keys stored in iCloud. A number of people have criticized Apple for this design, saying that they have effectively conceded the "Going Dark" encryption debate to the FBI. They didn't, and what they did was done for very valid business reasons -- but they're taking a serious risk... more

Problems With the Burr-Feinstein Bill

What appears to be a leaked copy of the Burr-Feinstein on encryption back doors. Crypto issues aside -- I and my co-authors have written on those before -- this bill has many other disturbing features. (Note: I've heard a rumor that this is an old version. If so, I'll update this post as necessary when something is actually introduced.) One of the more amazing oddities is that the bill's definition of "communications" (page 6, line 10) includes "oral communication", as defined in 18 USC 2510. more

The FBI and the iPhone: Important Unanswered Questions

As you probably know, the FBI has gotten into Syed Farook's iPhone. Many people have asked the obvious questions: how did the FBI do it, will they tell Apple, did they find anything useful, etc.? I think there are deeper questions that really get to the full import of the break. How expensive is the attack? Security - and by extension, insecurity - are not absolutes. Rather, they're only meaningful concepts if they include some notion of the cost of an attack. more

Why More Effort Won’t Solve the Exceptional Access Problem

In the debate over government "exceptional access" to encrypted communications, opponents with a technical bent (and that includes me) have said that it won't work: that such a scheme would inevitably lead to security problems. The response -- from the policy side, not from technical folk - has been to assert that perhaps more effort would suffice. FBI Director James Comey has said, "But my reaction to that is: I'm not sure they've really tried." Hillary Clinton wants a "Manhattan-like project, something that would bring the government and the tech communities together". More effort won't solve the problem - but the misunderstanding lies at the heart of why exceptional access is so hard. more

Cryptography is Hard

In the debate about "exceptional access" to encrypted conversations, law enforcement says they need such access to prevent and solve crimes; cryptographers, on the other hand, keep saying it's too complicated to do safely. That claim is sometimes met with skepticism: what's so hard about encryption? After all, you learn someone's key and just start encrypting, right? I wish it were that simple - but it's not. more

Why I Wrote ‘Thinking Security’

I have a new book out, Thinking Security: Stopping Next Year's Hackers. There are lots of security books out there today; why did I think another was needed? Two wellsprings nourished my muse. (The desire for that sort of poetic imagery was not among them.) The first was a deep-rooted dissatisfaction with common security advice. This common "wisdom" -- I use the word advisedly -- often seemed to be outdated. Yes, it was the distillation of years of conventional wisdom, but that was precisely the problem: the world has changed; the advice hasn't. more

I’m Shocked, Shocked to Find There’s Cryptanalysis Going On Here (Your plaintext, sir.)

There's been a lot of media attention in the last few days to a wonderful research paper on the weakness of 1024-bit Diffie-Hellman and on how the NSA can (and possibly does) exploit this. People seem shocked about the problem and appalled that the NSA would actually exploit it. Neither reaction is right. In the first place, the limitations of 1024-bit Diffie-Hellman have been known for a long time. RFC 3766, published in 2004, noted that a 1228-bit modulus had less than 80 bits of strength. That's clearly too little. more

Keys Under the Doormat

To those of us who have worked on crypto policy, the 1990s have become known as the Crypto Wars. The US government tried hard to control civilian use of cryptography. They tried to discourage academic research, restricted exports of cryptographic software, and -- most memorably -- pushed something called "escrowed encryption", a scheme wherein the government would have access to the short-term keys used to encrypt communications or stored files. more

Facebook and PGP

Facebook just announced support for PGP, an encrypted email standard, for email from them to you. It's an interesting move on many levels, albeit one that raises some interesting questions. The answers, and Facebook's possible follow-on moves, are even more interesting. The first question, of course, is why Facebook has done this. It will only appeal to a very small minority of users. Using encrypted email is not easy. more

Hacking: Users, Computers, and Systems

As many people have heard, there's been a security problem at the Internal Revenue Service. Some stories have used the word hack; other people, though, have complained that nothing was hacked, that the only problem was unauthorized access to taxpayer data but via authorized, intentionally built channels. The problem with this analysis is that it's looking at security from far too narrow a perspective... more

ISPs to Enforce Copyright Law

A group of major ISPs and major content providers have agreed on a a mechanism to enforce copyright laws in the network. While full details have not yet been released, the basic scheme involves using previously designed IP flags to denote public domain content. That is, given general copyright principles, it is on average a shorter code path and hence more efficient to set the flag on exempt material. more

Packet Loss: How the Internet Enforces Speed Limits

There's been a lot of controversy over the FCC's new Network Neutrality rules. Apart from the really big issues -- should there be such rules at all? Is reclassification the right way to accomplish it? -- one particular point has caught the eye of network engineers everywhere: the statement that packet loss should be published as a performance metric, with the consequent implication that ISPs should strive to achieve as low a value as possible. more

Hiding in the Firmware?

The most interesting feature of the newly-described "Equation Group" attacks has been the ability to hide malware in disk drive firmware. The threat is ghastly: you can wipe the disk and reinstall the operating system, but the modified firmware in the disk controller can reinstall nasties. A common response has been to suggest that firmware shouldn't be modifiable, unless a physical switch is activated. more

What Must We Trust?

My Twitter feed has exploded with the release of the Kaspersky report on the "Equation Group", an entity behind a very advanced family of malware. (Naturally, everyone is blaming the NSA. I don't know who wrote that code, so I'll just say it was beings from the Andromeda galaxy.) The Equation Group has used a variety of advanced techniques, including injecting malware into disk drive firmware, planting attack code on "photo" CDs sent to conference attendees, encrypting payloads... more

The Uses and Abuses of Cryptography

Another day, another data breach, and another round of calls for companies to encrypt their databases. Cryptography is a powerful tool, but in cases like this one it's not going to help. If your OS is secure, you don't need the crypto; if it's not, the crypto won't protect your data. In a case like the Anthem breach, the really sensitive databases are always in use. more

Software Insecurity: The Problem with the White House Cybersecurity Proposals

The White House has announced a new proposal to fix cybersecurity. Unfortunately, the positive effects will be minor at best; the real issue is not addressed. This is a serious missed opportunity by the Obama adminstration; it will expend a lot of political capital, to no real effect... The proposals focus on two things: improvements to the Computer Fraud and Abuse Act and provisions intended to encourage information sharing. At most, these will help at the margins; they'll do little to fix the underlying problems. more

Did the DPRK Hack Sony?

My Twitter feed has exploded with lots of theorizing about whether or not North Korea really hacked Sony. Most commentators are saying "no", pointing to the rather flimsy public evidence. They may be right -- but they may not be. Worse yet, we may never know the truth. One thing is quite certain, though: the "leaks" to the press about the NSA having concluded it was North Korea were not unauthorized leaks; rather, they were an official statement released without a name attached. more

If It Doesn’t Exist, It Can’t Be Abused

A number of outlets have reported that the U.S. Post Service was hacked, apparently by the Chinese government. The big question, of course, is why. It probably isn't for ordinary criminal reasons: The intrusion was carried out by "a sophisticated actor that appears not to be interested in identity theft or credit card fraud," USPS spokesman David Partenheimer said. ... But no customer credit card information from post offices or online purchases at usps.com was breached, they said. more

What Should PGP Look Like?

Those who care about security and usability - that is, those who care about security in the real world - have long known that PGP isn't usable by most people. It's not just a lack of user-friendliness, it's downright user hostile. Nor is modern professional crypto any better. What should be done? How should crypto in general, and PGP in particular, appear to the user? I don't claim to know, but let me pose a few questions. more

What Does “Network Neutrality” Mean?

A lot of ink and pixels have been spilled about the FCC's new rules for network neutrality. It's impossible to comment sensibly yet about the actual proposal, since as far as I know it's not been published anywhere, but the various news reports have left me confused about just what is being addressed. There are a number of different sorts of behavior that can result in performance differences to the end user... The purpose of this post is to give a simplified (with luck, not too horribly oversimplified) explanation of the different issues here. more

Doing Crypto

The recent discovery of the goto fail and heartbleed bugs has prompted some public discussion on a very important topic: what advice should cryptologists give to implementors who need to use crypto? What should they do? There are three parts to the answer: don't invent things; use ordinary care; and take special care around crypto code. more

Heartbleed: Don’t Panic

There's been a lot of ink and pixels spilled of late over the Heartbleed bug. Yes, it's serious. Yes, it potentially affects almost everyone. Yes, there are some precautions you should take. But there's good news, too: for many people, it's a non-event. Heartbleed allows an attacker to recover a random memory area from a web or email server running certain versions of OpenSSL. The question is what's in that memory. It may be nothing, or it may contain user passwords (this has reportedly been seen on Yahoo's mail service), cryptographic keys, etc. more

Fixing Holes

According to press reports, DHS is going to require federal computer contractors to scan for holes and start patching them within 72 hours. Is this feasible? It's certainly a useful goal. It's also extremely likely that it will take some important sites or applications off the air on occasion - patches are sometimes buggy (this is just the latest instance I've noticed), or they break a (typically non-guaranteeed or even accidental) feature that some critical software depends on. more

Password Leaks

The technical press is full of reports about the leak of a hashed password file from LinkedIn. Worse yet, we hear, the hashes weren't salted. The situation is probably both better and worse than it would appear; in any event, it's more complicated. more

Restricting Anti-Virus Won’t Work

In a blog post, Stewart Baker proposed restricting access to sophisticated anti-virus software as a way to limit the development of sophisticated malware. It won't work, for many different and independent reasons. To understand why, though, it's necessary to understand how AV programs work. The most important technology used today is the "signature" - a set of patterns of bytes - of each virus. Every commercial AV program on the market operates on a subscription model... more

Flame On!

Here we go again; another instance of really sophisticated spyware has been reported, a system that is "so complex and sophisticated that it's probably an advanced cyber-weapon unleashed by a wealthy country to wage a protracted espionage campaign on Iran". I won't get into the debate about whether or not it's really more impressive than Stuxnet, whether or not it's groundbreaking, or whether or not Israel launched it; let it suffice to say that there are dissenting views. I'm more interested in the implications. more

The Dangers of Asking for Social Network Passwords

In the last year or so, there's been a lot of controversy about some employers demanding social network passwords from employees or applicants. There's even been a bill introduced in Congress to bar the practice. The focus has been the privacy violation implied by such demands... The first issue is that a password gives the holder write access, not just read access, to the account. more

The FBI and Scotland Yard vs. Anonymous: Security Lessons

A lot of people are fascinated by the news story that Anonymous managed to listen to a conference call between the FBI and Scotland Yard. Some of the interest is due to marvel that two such sophisticated organizations could be had, some is due to schadenfreude, and some is probably despair: if the bad guys can get at these folks, is anyone safe? more

Types of Attack

A lot of pixels have been spilled in the last few years about "advanced persistent threats" (APT); if nothing else, any high-end company that has been penetrated wants to blame the attack on an APT. But what is an APT, other than (as best I can tell) an apparent codename for China? Do they exist? After thinking about it for a while, I came up with the following representation... more

Water Supply System Apparently Hacked, with Physical Damage

According to press reports, a water utility's SCADA network was hacked. The attacker turned a pump on and off too much, resulting in physical damage to the pump. ... For years, security specialists have been warning that something like this could happen. Although more and more people have started to believe it, we still hear all of the usual reassuring noises -- the hackers don't know enough, we have defenses, there are other safeguards, etc. That debate is now over... more

The Sins of the Flash

Recent news stories (based on research by Stanford student Feross Aboukhadijeh) state that an Adobe bug made it possible for remote sites to turn on a viewer's camera and microphone. That sounds bad enough, but that's not the really disturbing part. more

How to Abolish the DNS Hierarchy… But It’s a Bad Idea

There's been a fair amount of controversy of late about ICANN's decision to dramatically increase the number of top-level domains. With a bit of effort, though and with little disruption to the infrastructure -- we could abolish the issue entirely. Any string whatsoever could be used, and it would all Just Work. That is, it would Just Work in a narrow technical sense; it would hurt innovation and it would likely have serious economic failure modes. more

RSA Breach Fallout?

Back in March, it was widely reported that RSA had suffered a serious security breach that (to some extent) weakened the security of its SecurID token. However, the NY Times reported then that the chairman said that the penetration wasn't absolute but "it could potentially reduce the effectiveness of the system in the face of a 'broader attack.'". more

A Closer Look at Apple and Location-Tracking

There's been a lot of media attention to a report that iPhones track your movements. It's even reached the U.S. Senate. I'm underwhelmed. I think that the threat is overhyped. What is happening is that these devices create a hidden file with your location... more

The Worm and the Wiretap

According to recent news reports, the administration wants new laws to require that all communications systems contain "back doors" in their cryptosystems, ways for law enforcement and intelligence agencies to be able to read messages even though they're encrypted. By chance, there have also been articles on the Stuxnet computer worm, a very sophisticated piece of malware that many people are attributing to an arm of some government. The latter story shows why cryptographic back doors, known generically as "key escrow", are a bad idea. more

Clarke and Knake’s “Cyberwar”

I just finished reading Richard Clarke and Robert Knake's book Cyberwar. Though the book has flaws, some of them serious, the authors make some important points. They deserve to be taken seriously. I should note that I disagree with some of my friends about whether or not "cyberwar" is a real concept. Earlier, I speculated that perhaps it might be a useful way to conduct disinformation operations, but it need not be so limited. more

Comments on the National Strategy for Trusted Identities in Cyberspace

The White House has recently released a draft of the National Strategy for Trusted Identities in Cyberspace. Some of its ideas are good and some are bad. However, I fear it will be a large effort that will do little, and will pose a threat to our privacy. As I've written elsewhere, I may be willing to sacrifice some privacy to help the government protect the nation; I'm not willing to do so to help private companies track me when it's quite useless as a defense. more

Google, China, and Lawful Intercept

Like many people, I was taken by surprised by Google's announcement about its threatened withdrawal from China in the wake of continued censorship and attacks that appeared to emanate from there. My immediate reaction was quite simple: "Wow". There's been a lot of speculation about just why they pulled out. Some reports noted that Google has been losing market share to Baidu... I don't think, though, that that's the whole story. more

Why I Won’t Buy an E-book Reader - and When I Might

There have been many news stories lately about ebook readers. The New York Times said that they were prominently featured at the Consumer Electronics Show. Amazon is pushing its Kindle; Barnes and Noble has its Nook. There are many other aspirants, either on the market now or waiting in the wings. For now, though, I'm sitting on the sidelines. more

The Real Face of Cyberwar?

Anyone who reads the papers sees stories -- or hype -- about cyberwarfare. Can it happen? Has it already happened, in Estonia or Georgia? There has even been a Rand Corporation study on cyberwarfare and cyberdeterrence. I wonder, though, if real cyberwarfare might be more subtle -- perhaps a "cyber cold war"? more

Congress and Peer-to-Peer Filesharing

Some members of Congress have gotten extremely upset about peer-to-peer filesharing. Even the New York Times has editorialized about the issue. The problem of files leaking out is a real one, but the bills are misguided. Fundamentally, the real issue is that files are being shared without the user intending that result... more

The Role of a Cybersecurity Czar

For years now, there have been calls for a high-level cybersecurity official, preferably reporting directly to the president. This has never happened. Indeed, there is a lot of unhappiness in some circles that President Obama has not appointed anyone as "czar" (or czarina), despite the early fanfare about the 60-day cybersecurity review. There are many reasons why nothing has happened... more

Skype’s End User License Agreement

I was looking at the End User License Agreement to which Skype wants people to assent. I noticed the following odd provision (Section 3.2.4): You hereby grant to Skype a non-exclusive, worldwide, perpetual, irrevocable, royalty-free, sublicensable and transferable licence to Use the Content in any media in connection with the Skype Software, the Products and the Skype Website. more

The Cybersecurity Act of 2009

Four senators (Rockefeller, Bayh, Nelson, and Snowe) have recently introduced S.773, the Cybersecurity Act of 2009. While there are some good parts to the bill, many of the substantive provisions are poorly thought out at best. The bill attempts to solve non-problems, and to assume that research results can be commanded into being by virtue of an act of Congress. Beyond that, there are parts of the bill whose purpose is mysterious, or whose content bears no relation to its title. more

Internet Records Retention Bill

A lot of pixels have been spilled lately over an Internet records retention bill recently introduced in both the House and the Senate. The goal is to fight child pornography. That's a worthwhile goal; however, I think these bills will do little to further it. Worse yet, I think that at least two of the provisions of the bill are likely to have bad side effects... more

YouTube, the Government, and Privacy

It was just announced that every member of Congress will be able to create his or her own channel on YouTube. Viewers can go to the House or Senate home pages and navigate via a map to find the videos they're interested in. While it is good that citizens will have more insight into what their Senators and Representatives think, the way this is being done poses a serious privacy risk. more

A Telegraph-Era TLD?

While doing research for a paper on telegraph codebooks, I was reminded of something I had long known: one could have short addresses for telegrams. A short article in The New Yorker described how it worked in New York City. Briefly, one could pick more or less any name that wasn't in use, and list it with the Central Bureau for Registered Addresses... more

The Report on “Securing Cyberspace for the 44th Presidency”

A report "Securing Cyberspace for the 44th Presidency" has just been released. While I don't agree with everything it says (and in fact I strongly disagree with some parts of it), I regard it as required reading for anyone interested in cybersecurity and public policy. The analysis of the threat environment is, in my opinion, superb; I don't think I've seen it explicated better. Briefly, the US is facing threats at all levels, from individual cybercriminals to actions perpetrated by nation-states. The report pulls no punches... more

Cybercrime and “Remote Search”

According to news reports, part of the EU's cybercrime strategy is "remote search" of suspects' computers. I'm not 100% certain what that means, but likely guesses are alarming. The most obvious interpretation is also the most alarming: that some police officer will have the right and the ability to peruse people's computers from his or her desktop. How, precisely, is this to be done? Will Microsoft and Apple – and Ubuntu and Red Hat and all the BSDs and everyone else who ships systems – have to build back doors into all operating systems? more