Entries Tagged "Google"

Page 8 of 19

Should We Allow Bulk Searching of Cloud Archives?

Jonathan Zittrain proposes a very interesting hypothetical:

Suppose a laptop were found at the apartment of one of the perpetrators of last year’s Paris attacks. It’s searched by the authorities pursuant to a warrant, and they find a file on the laptop that’s a set of instructions for carrying out the attacks.

The discovery would surely help in the prosecution of the laptop’s owner, tying him to the crime. But a junior prosecutor has a further idea. The private document was likely shared among other conspirators, some of whom are still on the run or unknown entirely. Surely Google has the ability to run a search of all Gmail inboxes, outboxes, and message drafts folders, plus Google Drive cloud storage, to see if any of its 900 million users are currently in possession of that exact document. If Google could be persuaded or ordered to run the search, it could generate a list of only those Google accounts possessing the precise file ­ and all other Google users would remain undisturbed, except for the briefest of computerized “touches” on their accounts to see if the file reposed there.

He then goes through the reasons why Google should run the search, and then reasons why Google shouldn’t—and finally says what he would do.

I think it’s important to think through hypotheticals like this before they happen. We’re better able to reason about them now, when they are just hypothetical.

Posted on January 16, 2016 at 5:26 AMView Comments

A History of Privacy

This New Yorker article traces the history of privacy from the mid 1800s to today:

As a matter of historical analysis, the relationship between secrecy and privacy can be stated in an axiom: the defense of privacy follows, and never precedes, the emergence of new technologies for the exposure of secrets. In other words, the case for privacy always comes too late. The horse is out of the barn. The post office has opened your mail. Your photograph is on Facebook. Google already knows that, notwithstanding your demographic, you hate kale.

Posted on November 30, 2015 at 12:47 PMView Comments

How GCHQ Tracks Internet Users

The Intercept has a new story from the Snowden documents about the UK’s surveillance of the Internet by the GCHQ:

The mass surveillance operation ­ code-named KARMA POLICE­ was launched by British spies about seven years ago without any public debate or scrutiny. It was just one part of a giant global Internet spying apparatus built by the United Kingdom’s electronic eavesdropping agency, Government Communications Headquarters, or GCHQ.

[…]

One system builds profiles showing people’s web browsing histories. Another analyzes instant messenger communications, emails, Skype calls, text messages, cell phone locations, and social media interactions. Separate programs were built to keep tabs on “suspicious” Google searches and usage of Google Maps.

[…]

As of March 2009, the largest slice of data Black Hole held—41 percent—was about people’s Internet browsing histories. The rest included a combination of email and instant messenger records, details about search engine queries, information about social media activity, logs related to hacking operations, and data on people’s use of tools to browse the Internet anonymously.

Lots more in the article. The Intercept also published 28 new top secret NSA and GCHQ documents.

Posted on September 29, 2015 at 6:16 AMView Comments

Stagefright Vulnerability in Android Phones

The Stagefright vulnerability for Android phones is a bad one. It’s exploitable via a text message (details depend on auto downloading of the particular phone), it runs at an elevated privilege (again, the severity depends on the particular phone—on some phones it’s full privilege), and it’s trivial to weaponize. Imagine a worm that infects a phone and then immediately sends a copy of itself to everyone on that phone’s contact list.

The worst part of this is that it’s an Android exploit, so most phones won’t be patched anytime soon—if ever. (The people who discovered the bug alerted Google in April. Google has sent patches to its phone manufacturer partners, but most of them have not sent the patch to Android phone users.)

Posted on July 28, 2015 at 6:37 AMView Comments

Google's Unguessable URLs

Google secures photos using public but unguessable URLs:

So why is that public URL more secure than it looks? The short answer is that the URL is working as a password. Photos URLs are typically around 40 characters long, so if you wanted to scan all the possible combinations, you’d have to work through 1070 different combinations to get the right one, a problem on an astronomical scale. “There are enough combinations that it’s considered unguessable,” says Aravind Krishnaswamy, an engineering lead on Google Photos. “It’s much harder to guess than your password.”

It’s a perfectly valid security measure, although unsettling to some.

Posted on July 20, 2015 at 5:25 AMView Comments

Protecting Against Google Phishing in Chrome

Google has a new Chrome extension called “Password Alert”:

To help keep your account safe, today we’re launching Password Alert, a free, open-source Chrome extension that protects your Google and Google Apps for Work Accounts. Once you’ve installed it, Password Alert will show you a warning if you type your Google password into a site that isn’t a Google sign-in page. This protects you from phishing attacks and also encourages you to use different passwords for different sites, a security best practice.

Here’s how it works for consumer accounts. Once you’ve installed and initialized Password Alert, Chrome will remember a “scrambled” version of your Google Account password. It only remembers this information for security purposes and doesn’t share it with anyone. If you type your password into a site that isn’t a Google sign-in page, Password Alert will show you a notice like the one below. This alert will tell you that you’re at risk of being phished so you can update your password and protect yourself.

It’s a clever idea. Of course it’s not perfect, and doesn’t completely solve the problem. But it’s an easy security improvement, and one that should be generalized to non-Google sites. (Although it’s not uncommon for the security of many passwords to be tied to the security of the e-mail account.) It reminds me somewhat of cert pinning; in both cases, the browser uses independent information to verify what the network is telling it.

Slashdot thread.

EDITED TO ADD: It’s not even a day old, and there’s an attack.

Posted on April 30, 2015 at 9:11 AMView Comments

Hardware Bit-Flipping Attack

The Project Zero team at Google has posted details of a new attack that targets a computer’s’ DRAM. It’s called Rowhammer. Here’s a good description:

Here’s how Rowhammer gets its name: In the Dynamic Random Access Memory (DRAM) used in some laptops, a hacker can run a program designed to repeatedly access a certain row of transistors in the computer’s memory, “hammering” it until the charge from that row leaks into the next row of memory. That electromagnetic leakage can cause what’s known as “bit flipping,” in which transistors in the neighboring row of memory have their state reversed, turning ones into zeros or vice versa. And for the first time, the Google researchers have shown that they can use that bit flipping to actually gain unintended levels of control over a victim computer. Their Rowhammer hack can allow a “privilege escalation,” expanding the attacker’s influence beyond a certain fenced-in portion of memory to more sensitive areas.

Basically:

When run on a machine vulnerable to the rowhammer problem, the process was able to induce bit flips in page table entries (PTEs). It was able to use this to gain write access to its own page table, and hence gain read-write access to all of physical memory.

The cause is simply the super dense packing of chips:

This works because DRAM cells have been getting smaller and closer together. As DRAM manufacturing scales down chip features to smaller physical dimensions, to fit more memory capacity onto a chip, it has become harder to prevent DRAM cells from interacting electrically with each other. As a result, accessing one location in memory can disturb neighbouring locations, causing charge to leak into or out of neighbouring cells. With enough accesses, this can change a cell’s value from 1 to 0 or vice versa.

Very clever, and yet another example of the security interplay between hardware and software.

This kind of thing is hard to fix, although the Google team gives some mitigation techniques at the end of their analysis.

Slashdot thread.

EDITED TO ADD (3/12): Good explanation of the vulnerability.

Posted on March 11, 2015 at 6:16 AMView Comments

1 6 7 8 9 10 19

Sidebar photo of Bruce Schneier by Joe MacInnis.