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There’s a Kickstarter for a sticker that you can stick on a glove and then register with a biometric access system like an iPhone. It’s an interesting security trade-off: swapping something you are (the biometric) with something you have (the glove).
Gizmodo story.
This is exactly the sort of Internet-of-Things attack that has me worried:
“IoT Goes Nuclear: Creating a ZigBee Chain Reaction” by Eyal Ronen, Colin OFlynn, Adi Shamir and Achi-Or Weingarten.
Abstract: Within the next few years, billions of IoT devices will densely populate our cities. In this paper we describe a new type of threat in which adjacent IoT devices will infect each other with a worm that will spread explosively over large areas in a kind of nuclear chain reaction, provided that the density of compatible IoT devices exceeds a certain critical mass. In particular, we developed and verified such an infection using the popular Philips Hue smart lamps as a platform. The worm spreads by jumping directly from one lamp to its neighbors, using only their built-in ZigBee wireless connectivity and their physical proximity. The attack can start by plugging in a single infected bulb anywhere in the city, and then catastrophically spread everywhere within minutes, enabling the attacker to turn all the city lights on or off, permanently brick them, or exploit them in a massive DDOS attack. To demonstrate the risks involved, we use results from percolation theory to estimate the critical mass of installed devices for a typical city such as Paris whose area is about 105 square kilometers: The chain reaction will fizzle if there are fewer than about 15,000 randomly located smart lights in the whole city, but will spread everywhere when the number exceeds this critical mass (which had almost certainly been surpassed already).
To make such an attack possible, we had to find a way to remotely yank already installed lamps from their current networks, and to perform over-the-air firmware updates. We overcame the first problem by discovering and exploiting a major bug in the implementation of the Touchlink part of the ZigBee Light Link protocol, which is supposed to stop such attempts with a proximity test. To solve the second problem, we developed a new version of a side channel attack to extract the global AES-CCM key that Philips uses to encrypt and authenticate new firmware. We used only readily available equipment costing a few hundred dollars, and managed to find this key without seeing any actual updates. This demonstrates once again how difficult it is to get security right even for a large company that uses standard cryptographic techniques to protect a major product.
New research: “Flip Feng Shui: Hammering a Needle in the Software Stack,” by Kaveh Razavi, Ben Gras, Erik Bosman Bart Preneel, Cristiano Giuffrida, and Herbert Bos.
Abstract: We introduce Flip Feng Shui (FFS), a new exploitation vector which allows an attacker to induce bit flips over arbitrary physical memory in a fully controlled way. FFS relies on hardware bugs to induce bit flips over memory and on the ability to surgically control the physical memory layout to corrupt attacker-targeted data anywhere in the software stack. We show FFS is possible today with very few constraints on the target data, by implementing an instance using the Rowhammer bug and memory deduplication (an OS feature widely deployed in production). Memory deduplication allows an attacker to reverse-map any physical page into a virtual page she owns as long as the page’s contents are known. Rowhammer, in turn, allows an attacker to flip bits in controlled (initially unknown) locations in the target page.
We show FFS is extremely powerful: a malicious VM in a practical cloud setting can gain unauthorized access to a co-hosted victim VM running OpenSSH. Using FFS, we exemplify end-to-end attacks breaking OpenSSH public-key authentication, and forging GPG signatures from trusted keys, thereby compromising the Ubuntu/Debian update mechanism. We conclude by discussing mitigations and future directions for FFS attacks.
NIST is no longer recommending two-factor authentication systems that use SMS, because of their many insecurities. In the latest draft of its Digital Authentication Guideline, there’s the line:
[Out of band verification] using SMS is deprecated, and will no longer be allowed in future releases of this guidance.
Google is trying to bring this to Android developers by the end of the year:
Today, secure logins—like those used by banks or in the enterprise environment—often require more than just a username and password. They tend to also require the entry of a unique PIN, which is generally sent to your phone via SMS or emailed. This is commonly referred to as two-factor authentication, as it combines something you know (your password) with something you have in your possession, like your phone.
With Project Abacus, users would instead unlock devices or sign into applications based on a cumulative “Trust Score.” This score would be calculated using a variety of factors, including your typing patterns, current location, speed and voice patterns, facial recognition, and other things.
Basically, the system replaces traditional authentication—something you know, have, or are—with surveillance. So maybe this is a good idea, and maybe it isn’t. The devil is in the details.
EDITED TO ADD: It’s being called creepy. But, as we’ve repeatedly learned, creepy is subjective. What’s creepy now is perfectly normal two years later.
Interesting research: Abdul Serwadda, Vir V. Phoha, Zibo Wang, Rajesh Kumar, and Diksha Shukla, “Robotic Robbery on the Touch Screen,” ACM Transactions on Information and System Security, May 2016.
Abstract: Despite the tremendous amount of research fronting the use of touch gestures as a mechanism of continuous authentication on smart phones, very little research has been conducted to evaluate how these systems could behave if attacked by sophisticated adversaries. In this article, we present two Lego-driven robotic attacks on touch-based authentication: a population statistics-driven attack and a user-tailored attack. The population statistics-driven attack is based on patterns gleaned from a large population of users, whereas the user-tailored attack is launched based on samples stolen from the victim. Both attacks are launched by a Lego robot that is trained on how to swipe on the touch screen. Using seven verification algorithms and a large dataset of users, we show that the attacks cause the system’s mean false acceptance rate (FAR) to increase by up to fivefold relative to the mean FAR seen under the standard zero-effort impostor attack. The article demonstrates the threat that robots pose to touch-based authentication and provides compelling evidence as to why the zero-effort attack should cease to be used as the benchmark for touch-based authentication systems.
A criminal ring was arrested in Malaysia for credit card fraud:
They would visit the online shopping websites and purchase all their items using phony credit card details while the debugging app was activated.
The app would fetch the transaction data from the bank to the online shopping website, and trick the website into believing that the transaction was approved, when in reality, it had been declined by the bank.
The syndicates would later sell the items they had purchased illegally for a much lower price.
The problem here seems to be bad systems design. Why should the user be able to spoof the merchant’s verification protocol with the bank?
Traditional computer security concerns itself with vulnerabilities. We employ antivirus software to detect malware that exploits vulnerabilities. We have automatic patching systems to fix vulnerabilities. We debate whether the FBI should be permitted to introduce vulnerabilities in our software so it can get access to systems with a warrant. This is all important, but what’s missing is a recognition that software vulnerabilities aren’t the most common attack vector: credential stealing is.
The most common way hackers of all stripes, from criminals to hacktivists to foreign governments, break into networks is by stealing and using a valid credential. Basically, they steal passwords, set up man-in-the-middle attacks to piggy-back on legitimate logins, or engage in cleverer attacks to masquerade as authorized users. It’s a more effective avenue of attack in many ways: it doesn’t involve finding a zero-day or unpatched vulnerability, there’s less chance of discovery, and it gives the attacker more flexibility in technique.
Rob Joyce, the head of the NSA’s Tailored Access Operations (TAO) group—basically the country’s chief hacker—gave a rare public talk at a conference in January. In essence, he said that zero-day vulnerabilities are overrated, and credential stealing is how he gets into networks: “A lot of people think that nation states are running their operations on zero days, but it’s not that common. For big corporate networks, persistence and focus will get you in without a zero day; there are so many more vectors that are easier, less risky, and more productive.”
This is true for us, and it’s also true for those attacking us. It’s how the Chinese hackers breached the Office of Personnel Management in 2015. The 2014 criminal attack against Target Corporation started when hackers stole the login credentials of the company’s HVAC vendor. Iranian hackers stole US login credentials. And the hacktivist that broke into the cyber-arms manufacturer Hacking Team and published pretty much every proprietary document from that company used stolen credentials.
As Joyce said, stealing a valid credential and using it to access a network is easier, less risky, and ultimately more productive than using an existing vulnerability, even a zero-day.
Our notions of defense need to adapt to this change. First, organizations need to beef up their authentication systems. There are lots of tricks that help here: two-factor authentication, one-time passwords, physical tokens, smartphone-based authentication, and so on. None of these is foolproof, but they all make credential stealing harder.
Second, organizations need to invest in breach detection and—most importantly—incident response. Credential-stealing attacks tend to bypass traditional IT security software. But attacks are complex and multi-step. Being able to detect them in process, and to respond quickly and effectively enough to kick attackers out and restore security, is essential to resilient network security today.
Vulnerabilities are still critical. Fixing vulnerabilities is still vital for security, and introducing new vulnerabilities into existing systems is still a disaster. But strong authentication and robust incident response are also critical. And an organization that skimps on these will find itself unable to keep its networks secure.
This essay originally appeared on Xconomy.
EDITED TO ADD (5/23): Portuguese translation.
Interesting research: “CPV: Delay-based Location Verification for the Internet“:
Abstract: The number of location-aware services over the Internet continues growing. Some of these require the client’s geographic location for security-sensitive applications. Examples include location-aware authentication, location-aware access policies, fraud prevention, complying with media licensing, and regulating online gambling/voting. An adversary can evade existing geolocation techniques, e.g., by faking GPS coordinates or employing a non-local IP address through proxy and virtual private networks. We devise Client Presence Verification (CPV), a delay-based verification technique designed to verify an assertion about a device’s presence inside a prescribed geographic region. CPV does not identify devices by their IP addresses. Rather, the device’s location is corroborated in a novel way by leveraging geometric properties of triangles, which prevents an adversary from manipulating measured delays. To achieve high accuracy, CPV mitigates Internet path asymmetry using a novel method to deduce one-way application-layer delays to/from the client’s participating device, and mines these delays for evidence supporting/refuting the asserted location. We evaluate CPV through detailed experiments on PlanetLab, exploring various factors that affect its efficacy, including the granularity of the verified location, and the verification time. Results highlight the potential of CPV for practical adoption.
Brian Krebs has the story. Bottom line: PayPal has no excuse for this kind of stuff. I hope the public shaming incents them to offer better authentication for their customers.
Sidebar photo of Bruce Schneier by Joe MacInnis.