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The digital forensics company Cellebrite now claims it can unlock any iPhone.
I dithered before blogging this, not wanting to give the company more publicity. But I decided that everyone who wants to know already knows, and that Apple already knows. It’s all of us that need to know.
Long news article (alternate source) on iPhone privacy, specifically the enormous amount of data your apps are collecting without your knowledge. A lot of this happens in the middle of the night, when you’re probably not otherwise using your phone:
IPhone apps I discovered tracking me by passing information to third parties just while I was asleep include Microsoft OneDrive, Intuit’s Mint, Nike, Spotify, The Washington Post and IBM’s the Weather Channel. One app, the crime-alert service Citizen, shared personally identifiable information in violation of its published privacy policy.
And your iPhone doesn’t only feed data trackers while you sleep. In a single week, I encountered over 5,400 trackers, mostly in apps, not including the incessant Yelp traffic.
Matthew Green intelligently speculates about how Apple’s new “Find My” feature works.
If you haven’t already been inspired by the description above, let me phrase the question you ought to be asking: how is this system going to avoid being a massive privacy nightmare?
Let me count the concerns:
- If your device is constantly emitting a BLE signal that uniquely identifies it, the whole world is going to have (yet another) way to track you. Marketers already use WiFi and Bluetooth MAC addresses to do this: Find My could create yet another tracking channel.
- It also exposes the phones who are doing the tracking. These people are now going to be sending their current location to Apple (which they may or may not already be doing). Now they’ll also be potentially sharing this information with strangers who “lose” their devices. That could go badly.
- Scammers might also run active attacks in which they fake the location of your device. While this seems unlikely, people will always surprise you.
The good news is that Apple claims that their system actually does provide strong privacy, and that it accomplishes this using clever cryptography. But as is typical, they’ve declined to give out the details how they’re going to do it. Andy Greenberg talked me through an incomplete technical description that Apple provided to Wired, so that provides many hints. Unfortunately, what Apple provided still leaves huge gaps. It’s into those gaps that I’m going to fill in my best guess for what Apple is actually doing.
“Hey Siri; I’m getting pulled over” can be a shortcut:
Once the shortcut is installed and configured, you just have to say, for example, “Hey Siri, I’m getting pulled over.” Then the program pauses music you may be playing, turns down the brightness on the iPhone, and turns on “do not disturb” mode.
It also sends a quick text to a predetermined contact to tell them you’ve been pulled over, and it starts recording using the iPhone’s front-facing camera. Once you’ve stopped recording, it can text or email the video to a different predetermined contact and save it to Dropbox.
This clever attack allows someone to uniquely identify a phone when you visit a website, based on data from the accelerometer, gyroscope, and magnetometer sensors.
We have developed a new type of fingerprinting attack, the calibration fingerprinting attack. Our attack uses data gathered from the accelerometer, gyroscope and magnetometer sensors found in smartphones to construct a globally unique fingerprint. Overall, our attack has the following advantages:
- The attack can be launched by any website you visit or any app you use on a vulnerable device without requiring any explicit confirmation or consent from you.
- The attack takes less than one second to generate a fingerprint.
- The attack can generate a globally unique fingerprint for iOS devices.
- The calibration fingerprint never changes, even after a factory reset.
- The attack provides an effective means to track you as you browse across the web and move between apps on your phone.
* Following our disclosure, Apple has patched this vulnerability in iOS 12.2.
Research paper.
This is kind of a crazy iPhone vulnerability: it’s possible to call someone on FaceTime and listen on their microphone—and see from their camera—before they accept the call.
This is definitely an embarrassment, and Apple was right to disable Group FaceTime until it’s fixed. But it’s hard to imagine how an adversary can operationalize this in any useful way.
New York governor Andrew M. Cuomo wrote: “The FaceTime bug is an egregious breach of privacy that puts New Yorkers at risk.” Kinda, I guess.
EDITED TO ADD (1/30): This bug/vulnerability was first discovered by a 14-year-old, whose mother tried to alert Apple with no success.
This is really just to point out that computer security is really hard:
Almost as soon as Apple released iOS 12.1 on Tuesday, a Spanish security researcher discovered a bug that exploits group Facetime calls to give anyone access to an iPhone users’ contact information with no need for a passcode.
[…]
A bad actor would need physical access to the phone that they are targeting and has a few options for viewing the victim’s contact information. They would need to either call the phone from another iPhone or have the phone call itself. Once the call connects they would need to:
- Select the Facetime icon
- Select “Add Person”
- Select the plus icon
- Scroll through the contacts and use 3D touch on a name to view all contact information that’s stored.
Making the phone call itself without entering a passcode can be accomplished by either telling Siri the phone number or, if they don’t know the number, they can say “call my phone.” We tested this with both the owners’ voice and a strangers voice, in both cases, Siri initiated the call.
Earlier this week, the New York Times reported that the Russians and the Chinese were eavesdropping on President Donald Trump’s personal cell phone and using the information gleaned to better influence his behavior. This should surprise no one. Security experts have been talking about the potential security vulnerabilities in Trump’s cell phone use since he became president. And President Barack Obama bristled at—but acquiesced to—the security rules prohibiting him from using a “regular” cell phone throughout his presidency.
Three broader questions obviously emerge from the story. Who else is listening in on Trump’s cell phone calls? What about the cell phones of other world leaders and senior government officials? And—most personal of all—what about my cell phone calls?
There are two basic places to eavesdrop on pretty much any communications system: at the end points and during transmission. This means that a cell phone attacker can either compromise one of the two phones or eavesdrop on the cellular network. Both approaches have their benefits and drawbacks. The NSA seems to prefer bulk eavesdropping on the planet’s major communications links and then picking out individuals of interest. In 2016, WikiLeaks published a series of classified documents listing “target selectors”: phone numbers the NSA searches for and records. These included senior government officials of Germany—among them Chancellor Angela Merkel—France, Japan, and other countries.
Other countries don’t have the same worldwide reach that the NSA has, and must use other methods to intercept cell phone calls. We don’t know details of which countries do what, but we know a lot about the vulnerabilities. Insecurities in the phone network itself are so easily exploited that 60 Minutes eavesdropped on a US congressman’s phone live on camera in 2016. Back in 2005, unknown attackers targeted the cell phones of many Greek politicians by hacking the country’s phone network and turning on an already-installed eavesdropping capability. The NSA even implanted eavesdropping capabilities in networking equipment destined for the Syrian Telephone Company.
Alternatively, an attacker could intercept the radio signals between a cell phone and a tower. Encryption ranges from very weak to possibly strong, depending on which flavor the system uses. Don’t think the attacker has to put his eavesdropping antenna on the White House lawn; the Russian Embassy is close enough.
The other way to eavesdrop on a cell phone is by hacking the phone itself. This is the technique favored by countries with less sophisticated intelligence capabilities. In 2017, the public-interest forensics group Citizen Lab uncovered an extensive eavesdropping campaign against Mexican lawyers, journalists, and opposition politicians—presumably run by the government. Just last month, the same group found eavesdropping capabilities in products from the Israeli cyberweapons manufacturer NSO Group operating in Algeria, Bangladesh, Greece, India, Kazakhstan, Latvia, South Africa—45 countries in all.
These attacks generally involve downloading malware onto a smartphone that then records calls, text messages, and other user activities, and forwards them to some central controller. Here, it matters which phone is being targeted. iPhones are harder to hack, which is reflected in the prices companies pay for new exploit capabilities. In 2016, the vulnerability broker Zerodium offered $1.5 million for an unknown iOS exploit and only $200K for a similar Android exploit. Earlier this year, a new Dubai start-up announced even higher prices. These vulnerabilities are resold to governments and cyberweapons manufacturers.
Some of the price difference is due to the ways the two operating systems are designed and used. Apple has much more control over the software on an iPhone than Google does on an Android phone. Also, Android phones are generally designed, built, and sold by third parties, which means they are much less likely to get timely security updates. This is changing. Google now has its own phone—Pixel—that gets security updates quickly and regularly, and Google is now trying to pressure Android-phone manufacturers to update their phones more regularly. (President Trump reportedly uses an iPhone.)
Another way to hack a cell phone is to install a backdoor during the design process. This is a real fear; earlier this year, US intelligence officials warned that phones made by the Chinese companies ZTE and Huawei might be compromised by that government, and the Pentagon ordered stores on military bases to stop selling them. This is why China’s recommendation that if Trump wanted security, he should use a Huawei phone, was an amusing bit of trolling.
Given the wealth of insecurities and the array of eavesdropping techniques, it’s safe to say that lots of countries are spying on the phones of both foreign officials and their own citizens. Many of these techniques are within the capabilities of criminal groups, terrorist organizations, and hackers. If I were guessing, I’d say that the major international powers like China and Russia are using the more passive interception techniques to spy on Trump, and that the smaller countries are too scared of getting caught to try to plant malware on his phone.
It’s safe to say that President Trump is not the only one being targeted; so are members of Congress, judges, and other senior officials—especially because no one is trying to tell any of them to stop using their cell phones (although cell phones still are not allowed on either the House or the Senate floor).
As for the rest of us, it depends on how interesting we are. It’s easy to imagine a criminal group eavesdropping on a CEO’s phone to gain an advantage in the stock market, or a country doing the same thing for an advantage in a trade negotiation. We’ve seen governments use these tools against dissidents, reporters, and other political enemies. The Chinese and Russian governments are already targeting the US power grid; it makes sense for them to target the phones of those in charge of that grid.
Unfortunately, there’s not much you can do to improve the security of your cell phone. Unlike computer networks, for which you can buy antivirus software, network firewalls, and the like, your phone is largely controlled by others. You’re at the mercy of the company that makes your phone, the company that provides your cellular service, and the communications protocols developed when none of this was a problem. If one of those companies doesn’t want to bother with security, you’re vulnerable.
This is why the current debate about phone privacy, with the FBI on one side wanting the ability to eavesdrop on communications and unlock devices, and users on the other side wanting secure devices, is so important. Yes, there are security benefits to the FBI being able to use this information to help solve crimes, but there are far greater benefits to the phones and networks being so secure that all the potential eavesdroppers—including the FBI—can’t access them. We can give law enforcement other forensics tools, but we must keep foreign governments, criminal groups, terrorists, and everyone else out of everyone’s phones. The president may be taking heat for his love of his insecure phone, but each of us is using just as insecure a phone. And for a surprising number of us, making those phones more private is a matter of national security.
This essay previously appeared in the Atlantic.
EDITED TO ADD: Steven Bellovin and Susan Landau have a good essay on the same topic, as does Wired. Slashdot post.
Recently, Apple introduced restricted mode to protect iPhones from attacks by companies like Cellebrite and Greyshift, which allow attackers to recover information from a phone without the password or fingerprint. Elcomsoft just announced that it can easily bypass it.
There is an important lesson in this: security is hard. Apple Computer has one of the best security teams on the planet. This feature was not tossed out in a day; it was designed and implemented with a lot of thought and care. If this team could make a mistake like this, imagine how bad a security feature is when implemented by a team without this kind of expertise.
This is the reason actual cryptographers and security engineers are very skeptical when a random company announces that their product is “secure.” We know that they don’t have the requisite security expertise to design and implement security properly. We know they didn’t take the time and care. We know that their engineers think they understand security, and designed to a level that they couldn’t break.
Getting security right is hard for the best teams on the world. It’s impossible for average teams.
Internet censors have a new strategy in their bid to block applications and websites: pressuring the large cloud providers that host them. These providers have concerns that are much broader than the targets of censorship efforts, so they have the choice of either standing up to the censors or capitulating in order to maximize their business. Today’s Internet largely reflects the dominance of a handful of companies behind the cloud services, search engines and mobile platforms that underpin the technology landscape. This new centralization radically tips the balance between those who want to censor parts of the Internet and those trying to evade censorship. When the profitable answer is for a software giant to acquiesce to censors’ demands, how long can Internet freedom last?
The recent battle between the Russian government and the Telegram messaging app illustrates one way this might play out. Russia has been trying to block Telegram since April, when a Moscow court banned it after the company refused to give Russian authorities access to user messages. Telegram, which is widely used in Russia, works on both iPhone and Android, and there are Windows and Mac desktop versions available. The app offers optional end-to-end encryption, meaning that all messages are encrypted on the sender’s phone and decrypted on the receiver’s phone; no part of the network can eavesdrop on the messages.
Since then, Telegram has been playing cat-and-mouse with the Russian telecom regulator Roskomnadzor by varying the IP address the app uses to communicate. Because Telegram isn’t a fixed website, it doesn’t need a fixed IP address. Telegram bought tens of thousands of IP addresses and has been quickly rotating through them, staying a step ahead of censors. Cleverly, this tactic is invisible to users. The app never sees the change, or the entire list of IP addresses, and the censor has no clear way to block them all.
A week after the court ban, Roskomnadzor countered with an unprecedented move of its own: blocking 19 million IP addresses, many on Amazon Web Services and Google Cloud. The collateral damage was widespread: The action inadvertently broke many other web services that use those platforms, and Roskomnadzor scaled back after it became clear that its action had affected services critical for Russian business. Even so, the censor is still blocking millions of IP addresses.
More recently, Russia has been pressuring Apple not to offer the Telegram app in its iPhone App Store. As of this writing, Apple has not complied, and the company has allowed Telegram to download a critical software update to iPhone users (after what the app’s founder called a delay last month). Roskomnadzor could further pressure Apple, though, including by threatening to turn off its entire iPhone app business in Russia.
Telegram might seem a weird app for Russia to focus on. Those of us who work in security don’t recommend the program, primarily because of the nature of its cryptographic protocols. In general, proprietary cryptography has numerous fatal security flaws. We generally recommend Signal for secure SMS messaging, or, if having that program on your computer is somehow incriminating, WhatsApp. (More than 1.5 billion people worldwide use WhatsApp.) What Telegram has going for it is that it works really well on lousy networks. That’s why it is so popular in places like Iran and Afghanistan. (Iran is also trying to ban the app.)
What the Russian government doesn’t like about Telegram is its anonymous broadcast feature—channel capability and chats—which makes it an effective platform for political debate and citizen journalism. The Russians might not like that Telegram is encrypted, but odds are good that they can simply break the encryption. Telegram’s role in facilitating uncontrolled journalism is the real issue.
Iran attempts to block Telegram have been more successful than Russia’s, less because Iran’s censorship technology is more sophisticated but because Telegram is not willing to go as far to defend Iranian users. The reasons are not rooted in business decisions. Simply put, Telegram is a Russian product and the designers are more motivated to poke Russia in the eye. Pavel Durov, Telegram’s founder, has pledged millions of dollars to help fight Russian censorship.
For the moment, Russia has lost. But this battle is far from over. Russia could easily come back with more targeted pressure on Google, Amazon and Apple. A year earlier, Zello used the same trick Telegram is using to evade Russian censors. Then, Roskomnadzor threatened to block all of Amazon Web Services and Google Cloud; and in that instance, both companies forced Zello to stop its IP-hopping censorship-evasion tactic.
Russia could also further develop its censorship infrastructure. If its capabilities were as finely honed as China’s, it would be able to more effectively block Telegram from operating. Right now, Russia can block only specific IP addresses, which is too coarse a tool for this issue. Telegram’s voice capabilities in Russia are significantly degraded, however, probably because high-capacity IP addresses are easier to block.
Whatever its current frustrations, Russia might well win in the long term. By demonstrating its willingness to suffer the temporary collateral damage of blocking major cloud providers, it prompted cloud providers to block another and more effective anti-censorship tactic, or at least accelerated the process. In April, Google and Amazon banned—and technically blocked—the practice of “domain fronting,” a trick anti-censorship tools use to get around Internet censors by pretending to be other kinds of traffic. Developers would use popular websites as a proxy, routing traffic to their own servers through another website—in this case Google.com—to fool censors into believing the traffic was intended for Google.com. The anonymous web-browsing tool Tor has used domain fronting since 2014. Signal, since 2016. Eliminating the capability is a boon to censors worldwide.
Tech giants have gotten embroiled in censorship battles for years. Sometimes they fight and sometimes they fold, but until now there have always been options. What this particular fight highlights is that Internet freedom is increasingly in the hands of the world’s largest Internet companies. And while freedom may have its advocates—the American Civil Liberties Union has tweeted its support for those companies, and some 12,000 people in Moscow protested against the Telegram ban—actions such as disallowing domain fronting illustrate that getting the big tech companies to sacrifice their near-term commercial interests will be an uphill battle. Apple has already removed anti-censorship apps from its Chinese app store.
In 1993, John Gilmore famously said that “The Internet interprets censorship as damage and routes around it.” That was technically true when he said it but only because the routing structure of the Internet was so distributed. As centralization increases, the Internet loses that robustness, and censorship by governments and companies becomes easier.
This essay previously appeared on Lawfare.com.
Sidebar photo of Bruce Schneier by Joe MacInnis.