November 23, 2017

HOWTO: Protect your small organization against electronic adversaries

October is “cyber security awareness month“. Among other notable announcements, Google just rolled out “advanced protection” — free for any Google account. So, in the spirit of offering pragmatic advice to real users, I wrote a short document that’s meant not for the usual Tinker audience but rather for the sort of person running a small non-profit, a political campaign, or even a small company.

If there’s one thing we learned from the leaks of the DNC emails during the 2016 presidential campaign it’s this: cyber-security matters. Whether or not you believe that the release of private campaign emails cost Clinton the election, they certainly influenced the process to the extent that any political campaign, any small non-profit, and any advocacy group has to now consider the possible impacts of cyber-attacks against their organizations. These could involve espionage (i.e., internal secrets being leaked) or sabotage (i.e., internal data being corrupted or destroyed). And your adversaries might be criminal hackers or foreign nation-state governments.

If you were a large multinational corporation, you’d have a dedicated team of security specialists to manage your organization. Unfortunately, you’re not and you can’t afford such a team. To help out, I’ve written a short document summarizing low-cost tactics you can take to reduce your vulnerabilities using simple techniques like two-factor authentication, so a stolen password isn’t enough for an attacker to log into your account. This document also recommends particular software and hardware configurations that move your organization “into the cloud” where providers like Google or Microsoft have security professionals who do much of the hard work on your behalf.

Enjoy!

https://www.cs.rice.edu/~dwallach/howto-electronic-adversaries.pdf

Why Making Johnny's Key Management Transparent is So Challenging

In light of the ongoing debate about the importance of using end-to-end encryption to protect our data and communications, several tech companies have announced plans to increase the encryption in their services. However, this isn’t a new pledge: since 2014, Google and Yahoo have been working on a browser plugin to facilitate sending encrypted emails using their services. Yet in recent weeks, some have criticized that only alpha releases of these tools exist, and have started asking why they’re still a work in progress.

One of the main challenges to building usable end-to-end encrypted communication tools is key management. Services such as Apple’s iMessage have made encrypted communication available to the masses with an excellent user experience because Apple manages a directory of public keys in a centralized server on behalf of their users. But this also means users have to trust that Apple’s key server won’t be compromised or compelled by hackers or nation-state actors to insert spurious keys to intercept and manipulate users’ encrypted messages. The alternative, and more secure, approach is to have the service provider delegate key management to the users so they aren’t vulnerable to a compromised centralized key server. This is how Google’s End-To-End works right now. But decentralized key management means users must “manually” verify each other’s keys to be sure that the keys they see for one another are valid, a process that several studies have shown to be cumbersome and error-prone for the vast majority of users. So users must make the choice between strong security and great usability.

In August 2015, we published our design for CONIKS, a key management system that addresses these usability and security issues. CONIKS makes the key management process transparent and publicly auditable. To evaluate the viability of CONIKS as a key management solution for existing secure communication services, we held design discussions with experts at Google, Yahoo, Apple and Open Whisper Systems, primarily over the course of 11 months (Nov ‘14 – Oct ‘15). From our conversations, we learned about the open technical challenges of deploying CONIKS in a real-world setting, and gained a better understanding for why implementing a transparent key management system isn’t a straightforward task.
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Why King George III Can Encrypt

[This is a guest post by Wenley Tong, Sebastian Gold, Samuel Gichohi, Mihai Roman, and Jonathan Frankle, undergraduates in the Privacy Technologies seminar that I offered for the second time in Spring 2014. They did an excellent class project on the usability of email encryption.]

PGP and similar email encryption standards have existed since the early 1990s, yet even in the age of NSA surveillance and ubiquitous data-privacy concerns, we continue to send email in plain text.  Researchers have attributed this apparent gaping hole in our security infrastructure to a deceivingly simple source: usability.  Email encryption, although cryptographically straightforward, appears too complicated for laypeople to understand.  In our project, we aimed to understand why this problem has eluded researchers for well over a decade and expand the design space of possible solutions to this and similar challenges at the intersection of security and usability.

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