Entries Tagged "academic papers"

Page 38 of 86

Teaching a Neural Network to Encrypt

Researchers have trained a neural network to encrypt its communications.

In their experiment, computers were able to make their own form of encryption using machine learning, without being taught specific cryptographic algorithms. The encryption was very basic, especially compared to our current human-designed systems. Even so, it is still an interesting step for neural nets, which the authors state “are generally not meant to be great at cryptography:.

This story is more about AI and neural networks than it is about cryptography. The algorithm isn’t any good, but is a perfect example of what I’ve heard called “Schneier’s Law“: Anyone can design a cipher that they themselves cannot break.

Research paper. Note that the researchers work at Google.

Posted on November 3, 2016 at 6:05 AMView Comments

Eavesdropping on Typing Over Voice-Over-IP

Interesting research: “Don’t Skype & Type! Acoustic Eavesdropping in Voice-Over-IP“:

Abstract: Acoustic emanations of computer keyboards represent a serious privacy issue. As demonstrated in prior work, spectral and temporal properties of keystroke sounds might reveal what a user is typing. However, previous attacks assumed relatively strong adversary models that are not very practical in many real-world settings. Such strong models assume: (i) adversary’s physical proximity to the victim, (ii) precise profiling of the victim’s typing style and keyboard, and/or (iii) significant amount of victim’s typed information (and its corresponding sounds) available to the adversary.

In this paper, we investigate a new and practical keyboard acoustic eavesdropping attack, called Skype & Type (S&T), which is based on Voice-over-IP (VoIP). S&T relaxes prior strong adversary assumptions. Our work is motivated by the simple observation that people often engage in secondary activities (including typing) while participating in VoIP calls. VoIP software can acquire acoustic emanations of pressed keystrokes (which might include passwords and other sensitive information) and transmit them to others involved in the call. In fact, we show that very popular VoIP software (Skype) conveys enough audio information to reconstruct the victim’s input ­ keystrokes typed on the remote keyboard. In particular, our results demonstrate
that, given some knowledge on the victim’s typing style and the keyboard, the attacker attains top-5 accuracy of 91:7% in guessing a random key pressed by the victim. (The accuracy goes down to still alarming 41:89% if the attacker is oblivious to both the typing style and the keyboard). Finally, we provide evidence that Skype & Type attack is robust to various VoIP issues (e.g., Internet bandwidth fluctuations and presence of voice over keystrokes), thus confirming feasibility of this attack.

News article.

Posted on October 28, 2016 at 5:24 AMView Comments

Hardware Bit-Flipping Attacks in Practice

A year and a half ago, I wrote about hardware bit-flipping attacks, which were then largely theoretical. Now, they can be used to root Android phones:

The breakthrough has the potential to make millions of Android phones vulnerable, at least until a security fix is available, to a new form of attack that seizes control of core parts of the operating system and neuters key security defenses. Equally important, it demonstrates that the new class of exploit, dubbed Rowhammer, can have malicious and far-reaching effects on a much wider number of devices than was previously known, including those running ARM chips.

Previously, some experts believed Rowhammer attacks that altered specific pieces of security-sensitive data weren’t reliable enough to pose a viable threat because exploits depended on chance hardware faults or advanced memory-management features that could be easily adapted to repel the attacks. But the new proof-of-concept attack developed by an international team of academic researchers is challenging those assumptions.

An app containing the researchers’ rooting exploit requires no user permissions and doesn’t rely on any vulnerability in Android to work. Instead, their attack exploits a hardware vulnerability, using a Rowhammer exploit that alters crucial bits of data in a way that completely roots name brand Android devices from LG, Motorola, Samsung, OnePlus, and possibly other manufacturers.

[…]

Drammer was devised by many of the same researchers behind Flip Feng Shui, and it adopts many of the same approaches. Still, it represents a significant improvement over Flip Feng Shui because it’s able to alter specific pieces of sensitive-security data using standard memory management interfaces built into the Android OS. Using crucial information about the layout of Android memory chips gleaned from a side channel the researchers discovered in ARM processors, Drammer is able to carry out what the researchers call a deterministic attack, meaning one that can reliably target security-sensitive data. The susceptibility of Android devices to Rowhammer exploits likely signals a similar vulnerability in memory chips used in iPhones and other mobile devices as well.

Here’s the paper.

And here’s the project’s website.

Posted on October 27, 2016 at 2:23 PMView Comments

How Different Stakeholders Frame Security

Josephine Wolff examines different Internet governance stakeholders and how they frame security debates.

Her conclusion:

The tensions that arise around issues of security among different groups of internet governance stakeholders speak to the many tangled notions of what online security is and whom it is meant to protect that are espoused by the participants in multistakeholder governance forums. What makes these debates significant and unique in the context of internet governance is not that the different stakeholders often disagree (indeed, that is a common occurrence), but rather that they disagree while all using the same vocabulary of security to support their respective stances. Government stakeholders advocate for limitations on WHOIS privacy/proxy services in order to aid law enforcement and protect their citizens from crime and fraud. Civil society stakeholders advocate against those limitations in order to aid activists and minorities and protect those online users from harassment. Both sides would claim that their position promotes a more secure internet and a more secure society—­and in a sense, both would be right, except that each promotes a differently secure internet and society, protecting different classes of people and behaviour from different threats.

While vague notions of security may be sufficiently universally accepted as to appear in official documents and treaties, the specific details of individual decisions­—such as the implementation of dotless domains, changes to the WHOIS database privacy policy, and proposals to grant government greater authority over how their internet traffic is routed­—require stakeholders to disentangle the many different ideas embedded in that language. For the idea of security to truly foster cooperation and collaboration as a boundary object in internet governance circles, the participating stakeholders will have to more concretely agree on what their vision of a secure internet is and how it will balance the different ideas of security espoused by different groups. Alternatively, internet governance stakeholders may find it more useful to limit their discussions on security, as a whole, and try to force their discussions to focus on more specific threats and issues within that space as a means of preventing themselves from succumbing to a façade of agreement without grappling with the sources of disagreement that linger just below the surface.

The intersection of multistakeholder internet governance and definitional issues of security is striking because of the way that the multistakeholder model both reinforces and takes advantage of the ambiguity surrounding the idea of security explored in the security studies literature. That ambiguity is a crucial component of maintaining a functional multistakeholder model of governance because it lends itself well to high-level agreements and discussions, contributing to the sense of consensus building across stakeholders. At the same time, gathering those different stakeholders together to decide specific issues related to the internet and its infrastructure brings to a fore the vast variety of definitions of security they employ and forces them to engage in security-versus-security fights, with each trying to promote their own particular notion of security. Security has long been a contested concept, but rarely do these contestations play out as directly and dramatically as in the multistakeholder arena of internet governance, where all parties are able to face off on what really constitutes security in a digital world.

We certainly saw this in the “going dark” debate: e.g. the FBI vs. Apple and their iPhone security.

Posted on October 24, 2016 at 6:03 AMView Comments

Quantum Tokens for Digital Signatures

This paper wins “best abstract” award: “Quantum Tokens for Digital Signatures,” by Shalev Ben David and Or Sattath:

Abstract: The fisherman caught a quantum fish. “Fisherman, please let me go,” begged the fish, “and I will grant you three wishes.” The fisherman agreed. The fish gave the fisherman a quantum computer, three quantum signing tokens and his classical public key.

The fish explained: “to sign your three wishes, use the tokenized signature scheme on this quantum computer, then show your valid signature to the king, who owes me a favor.”

The fisherman used one of the signing tokens to sign the document “give me a castle!” and rushed to the palace. The king executed the classical verification algorithm using the fish’s public key, and since it was valid, the king complied.

The fisherman’s wife wanted to sign ten wishes using their two remaining signing tokens. The fisherman did not want to cheat, and secretly sailed to meet the fish. “Fish, my wife wants to sign ten more wishes.”

But the fish was not worried: “I have learned quantum cryptography following the previous story (The Fisherman and His Wife by the brothers Grimm). The quantum tokens are consumed during the signing. Your polynomial wife cannot even sign four wishes using the three signing tokens I gave you.”

“How does it work?” wondered the fisherman.

“Have you heard of quantum money? These are quantum states which can be easily verified but are hard to copy. This tokenized quantum signature scheme extends Aaronson and Christiano’s quantum money scheme, which is why the signing tokens cannot be copied.”

“Does your scheme have additional fancy properties?” the fisherman asked.

“Yes, the scheme has other security guarantees: revocability, testability and everlasting security. Furthermore, if you’re at the sea and your quantum phone has only classical reception, you can use this scheme to transfer the value of the quantum money to shore,” said the fish, and swam his way.

Posted on October 6, 2016 at 7:03 AMView Comments

The Culture of Cybersecurity

Interesting survey of the cybersecurity culture in Norway.

96% of all Norwegian are online, more than 90% embrace new technology, and 6 of 10 feel capable of judging what is safe to do online. Still cyber-crime costs Norway approximately 19 billion NKR annually. At the same time 73.9% argue that the Internet will not be safer even if their personal computer is secure. We have also found that a majority of Norwegians accepts that their online activities may be monitored by the authorities. But less than half the population believe the Police is capable of helping them if they are subject to cybercrime, and 4 of 10 sees cyber activists (e.g. Anonymous) play a role in the fight against cybercrime and cyberwar. 44% of the participants in this study say that they have refrained from using an online service after they have learned about threats or security incidents. This should obviously influence digitalization policy.

Lots of details in the report.

Posted on October 3, 2016 at 6:23 AMView Comments

The Cost of Cyberattacks Is Less than You Might Think

Interesting research from Sasha Romanosky at RAND:

Abstract: In 2013, the US President signed an executive order designed to help secure the nation’s critical infrastructure from cyberattacks. As part of that order, he directed the National Institute for Standards and Technology (NIST) to develop a framework that would become an authoritative source for information security best practices. Because adoption of the framework is voluntary, it faces the challenge of incentivizing firms to follow along. Will frameworks such as that proposed by NIST really induce firms to adopt better security controls? And if not, why? This research seeks to examine the composition and costs of cyber events, and attempts to address whether or not there exist incentives for firms to improve their security practices and reduce the risk of attack. Specifically, we examine a sample of over 12 000 cyber events that include data breaches, security incidents, privacy violations, and phishing crimes. First, we analyze the characteristics of these breaches (such as causes and types of information compromised). We then examine the breach and litigation rate, by industry, and identify the industries that incur the greatest costs from cyber events. We then compare these costs to bad debts and fraud within other industries. The findings suggest that public concerns regarding the increasing rates of breaches and legal actions may be excessive compared to the relatively modest financial impact to firms that suffer these events. Public concerns regarding the increasing rates of breaches and legal actions, conflict, however, with our findings that show a much smaller financial impact to firms that suffer these events. Specifically, we find that the cost of a typical cyber incident in our sample is less than $200 000 (about the same as the firm’s annual IT security budget), and that this represents only 0.4% of their estimated annual revenues.

The result is that it often makes business sense to underspend on cybersecurity and just pay the costs of breaches:

Romanosky analyzed 12,000 incident reports and found that typically they only account for 0.4 per cent of a company’s annual revenues. That compares to billing fraud, which averages at 5 per cent, or retail shrinkage (ie, shoplifting and insider theft), which accounts for 1.3 per cent of revenues.

As for reputational damage, Romanosky found that it was almost impossible to quantify. He spoke to many executives and none of them could give a reliable metric for how to measure the PR cost of a public failure of IT security systems.

He also noted that the effects of a data incident typically don’t have many ramifications on the stock price of a company in the long term. Under the circumstances, it doesn’t make a lot of sense to invest too much in cyber security.

What’s being left out of these costs are the externalities. Yes, the costs to a company of a cyberattack are low to them, but there are often substantial additional costs borne by other people. The way to look at this is not to conclude that cybersecurity isn’t really a problem, but instead that there is a significant market failure that governments need to address.

Posted on September 29, 2016 at 6:51 AMView Comments

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Sidebar photo of Bruce Schneier by Joe MacInnis.