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Lawmakers and law enforcement agencies around the world, including in the United States, have increasingly called for backdoors in the encryption schemes that protect your data, arguing that national security is at stake. But new research indicates governments already have methods and tools that, for better or worse, let them access locked smartphones thanks to weaknesses in the security schemes of Android and iOS.

Cryptographers at Johns Hopkins University used publicly available documentation from Apple and Google as well as their own analysis to assess the robustness of Android and iOS encryption. They also studied more than a decade’s worth of reports about which of these mobile security features law enforcement and criminals have previously bypassed, or can currently, using special hacking tools…

once you unlock your device the first time after reboot, lots of encryption keys start getting stored in quick access memory, even while the phone is locked. At this point an attacker could find and exploit certain types of security vulnerabilities in iOS to grab encryption keys that are accessible in memory and decrypt big chunks of data from the phone. Based on available reports about smartphone access tools, like those from the Israeli law enforcement contractor Cellebrite and US-based forensic access firm Grayshift, the researchers realized that this is how almost all smartphone access tools likely work right now. It’s true that you need a specific type of operating system vulnerability to grab the keys — and both Apple and Google patch as many of those flaws as possible — but if you can find it, the keys are available, too…

Forensic tools exploiting the right vulnerability can grab even more decryption keys, and ultimately access even more data, on an Android phone.

Swiss politicians have voiced outrage and demanded an investigation after revelations that a second Swiss encryption company was allegedly used by the CIA and its German counterpart to spy on governments worldwide. “How can such a thing happen in a country that claims to be neutral like Switzerland?” co-head of Switzerland’s Socialist Party, Cedric Wermuth, asked in an interview with Swiss public broadcaster SRF late Thursday. He called for a parliamentary inquiry after an SRF investigation broadcast on Wednesday found that a second Swiss encryption firm had been part of a spectacular espionage scheme orchestrated by U.S. and German intelligence services.

A first investigation had revealed back in February an elaborate, decades-long set-up, in which the CIA and its German counterpart creamed off the top-secret communications of governments through their hidden control of a Swiss encryption company called Crypto.

SRF’s report this week found that a second but smaller Swiss encryption firm, Omnisec, had been used in the same way.

That company, which was split off from Swiss cryptographic equipment maker Gretag in 1987, sold voice, fax and data encryption equipment to governments around the world until it halted operations two years ago. SRF’s investigative program Rundschau concluded that, like Crypto, Omnisec had sold manipulated equipment to foreign governments and armies. Omnisec meanwhile also sold its faulty OC-500 series devices to several federal agencies in Switzerland, including its own intelligence agencies, as well as to Switzerland’s largest bank, UBS, and other private companies in the country, the SRF investigation showed.

The findings unleashed fresh outrage in Switzerland, which is still reeling from the Crypto revelations.

The Swiss intelligence service has known since at least 1993 that Switzerland-based encryption device maker Crypto AG was actually a front for the CIA and its German counterpart, according to a new report released by the Swiss Parliament, but Swiss leaders were in the dark until last year. From a report:
Switzerland’s intra-governmental information gap is unlikely to be welcome news in Europe, which already looks warily upon the U.S.’ expansive surveillance practices. Still, Crypto AG provided information of incalculable value to U.S. policymakers over many decades. Crypto AG was controlled from 1970 on by the CIA and the West German BND intelligence agency. It sold encryption devices — often employed in diplomatic communications — that were used by over 120 countries through the 2000s.

In a new Apple ad, a man on a city bus announces he has just shopped for divorce lawyers. Then a woman recites her credit card number through a megaphone in a park. “Some things shouldn’t be shared,” the ad says, “iPhone helps keep it that way.” Apple has built complex encryption into iPhones and made the devices’ security central to its marketing pitch. That, in turn, has angered law enforcement. Officials from the F.B.I. director to rural sheriffs have argued that encrypted phones stifle their work to catch and convict dangerous criminals. They have tried to force Apple and Google to unlock suspects’ phones, but the companies say they can’t. In response, the authorities have put their own marketing spin on the problem. Law enforcement, they say, is “going dark.” Yet new data reveals a twist to the encryption debate that undercuts both sides: Law enforcement officials across the nation regularly break into encrypted smartphones.

That is because at least 2,000 law enforcement agencies in all 50 states now have tools to get into locked, encrypted phones and extract their data, according to years of public records collected in a report by Upturn, a Washington nonprofit that investigates how the police use technology. At least 49 of the 50 largest U.S. police departments have the tools, according to the records, as do the police and sheriffs in small towns and counties across the country, including Buckeye, Ariz.; Shaker Heights, Ohio; and Walla Walla, Wash. And local law enforcement agencies that don’t have such tools can often send a locked phone to a state or federal crime lab that does. With more tools in their arsenal, the authorities have used them in an increasing range of cases, from homicides and rapes to drugs and shoplifting, according to the records, which were reviewed by The New York Times. Upturn researchers said the records suggested that U.S. authorities had searched hundreds of thousands of phones over the past five years. While the existence of such tools has been known for some time, the records show that the authorities break into phones far more than previously understood — and that smartphones, with their vast troves of personal data, are not as impenetrable as Apple and Google have advertised. While many in law enforcement have argued that smartphones are often a roadblock to investigations, the findings indicate that they are instead one of the most important tools for prosecutions.

Members of the intelligence-sharing alliance Five Eyes, along with government representatives for Japan and India, have published a statement over the weekend calling on tech companies to come up with a solution for law enforcement to access end-to-end encrypted communications. From a report:
The statement is the alliance’s latest effort to get tech companies to agree to encryption backdoors. The Five Eyes alliance, comprised of the US, the UK, Canada, Australia, and New Zealand, have made similar calls to tech giants in 2018 and 2019, respectively. Just like before, government officials claim tech companies have put themselves in a corner by incorporating end-to-end encryption (E2EE) into their products. If properly implemented, E2EE lets users have secure conversations — may them be chat, audio, or video — without sharing the encryption key with the tech companies. Representatives from the seven governments argue that the way E2EE encryption is currently supported on today’s major tech platforms prohibits law enforcement from investigating crime rings, but also the tech platforms themselves from enforcing their own terms of service. Signatories argue that “particular implementations of encryption technology” are currently posing challenges to law enforcement investigations, as the tech platforms themselves can’t access some communications and provide needed data to investigators.

privacytools.io provides knowledge and tools to protect your privacy against global mass surveillance.

Electronic Frontier Foundation’s Browser Privacy Tool checks if websites may be able to track you, even if you’ve limited or disabled cookies. Panopticlick tests your browser to see how unique it is based on the information it will share with sites it visits.

Encrypt your communications and end your reliance on proprietary services.

“WikiLeaks has unleashed a treasure trove of data to the internet, exposing information about the CIA’s arsenal of hacking tools. Code-named Vault 7, the first data is due to be released in serialized form, starting off with “Year Zero” as part one. A cache of over 8,500 documents and files has been made available via BitTorrent in an encrypted archive. Password to the files is:

SplinterItIntoAThousandPiecesAndScatterItIntoTheWinds

The documents reveal that the CIA worked with MI5 in the UK to infect Samsung smart TVs so their microphones could be turned on at will. Investigations were carried out into gaining control of modern cars and trucks, and there is even a specialized division of the CIA focused on accessing, controlling and exploiting iPhones and iPads. This and Android zero days enables the CIA to “to bypass the encryption of WhatsApp, Signal, Telegram, Wiebo, Confide and Cloackman by hacking the “smart” phones that they run on and collecting audio and message traffic before encryption is applied.”

“German researchers have discovered security flaws that could let hackers, spies and criminals listen to private phone calls and intercept text messages on a potentially massive scale – even when cellular networks are using the most advanced encryption now available.

The flaws, to be reported at a hacker conference in Hamburg this month, are the latest evidence of widespread insecurity on SS7, the global network that allows the world’s cellular carriers to route calls, texts and other services to each other. Experts say it’s increasingly clear that SS7, first designed in the 1980s, is riddled with serious vulnerabilities that undermine the privacy of the world’s billions of cellular customers.

The flaws discovered by the German researchers are actually functions built into SS7 for other purposes – such as keeping calls connected as users speed down highways, switching from cell tower to cell tower – that hackers can repurpose for surveillance because of the lax security on the network.

Those skilled at the myriad functions built into SS7 can locate callers anywhere in the world, listen to calls as they happen or record hundreds of encrypted calls and texts at a time for later decryption. There also is potential to defraud users and cellular carriers by using SS7 functions, the researchers say.

These vulnerabilities continue to exist even as cellular carriers invest billions of dollars to upgrade to advanced 3G technology aimed, in part, at securing communications against unauthorized eavesdropping. But even as individual carriers harden their systems, they still must communicate with each other over SS7, leaving them open to any of thousands of companies worldwide with access to the network. That means that a single carrier in Congo or Kazakhstan, for example, could be used to hack into cellular networks in the United States, Europe or anywhere else.

“It’s like you secure the front door of the house, but the back door is wide open,” said Tobias Engel, one of the German researchers.

Engel, founder of Sternraute, and Karsten Nohl, chief scientist for Security Research Labs, separately discovered these security weaknesses as they studied SS7 networks in recent months, after The Washington Post reported the widespread marketing of surveillance systems that use SS7 networks to locate callers anywhere in the world. The Post reported that dozens of nations had bought such systems to track surveillance targets and that skilled hackers or criminals could do the same using functions built into SS7. (The term is short for Signaling System 7 and replaced previous networks called SS6, SS5, etc.)

The researchers did not find evidence that their latest discoveries, which allow for the interception of calls and texts, have been marketed to governments on a widespread basis. But vulnerabilities publicly reported by security researchers often turn out to be tools long used by secretive intelligence services, such as the National Security Agency or Britain’s GCHQ, but not revealed to the public.

“Many of the big intelligence agencies probably have teams that do nothing but SS7 research and exploitation,” said Christopher Soghoian, principal technologist for the ACLU and an expert on surveillance technology. “They’ve likely sat on these things and quietly exploited them.”

The GSMA, a global cellular industry group based in London, did not respond to queries seeking comment about the vulnerabilities that Nohl and Engel have found. For the Post’s article in August on location tracking systems that use SS7, GSMA officials acknowledged problems with the network and said it was due to be replaced over the next decade because of a growing list of security and technical issues.

The German researchers found two distinct ways to eavesdrop on calls using SS7 technology. In the first, commands sent over SS7 could be used to hijack a cell phone’s “forwarding” function — a service offered by many carriers. Hackers would redirect calls to themselves, for listening or recording, and then onward to the intended recipient of a call. Once that system was in place, the hackers could eavesdrop on all incoming and outgoing calls indefinitely, from anywhere in the world.

The second technique requires physical proximity but could be deployed on a much wider scale. Hackers would use radio antennas to collect all the calls and texts passing through the airwaves in an area. For calls or texts transmitted using strong encryption, such as is commonly used for advanced 3G connections, hackers could request through SS7 that each caller’s carrier release a temporary encryption key to unlock the communication after it has been recorded.

Nohl on Wednesday demonstrated the ability to collect and decrypt a text message using the phone of a German senator, who cooperated in the experiment. But Nohl said the process could be automated to allow massive decryption of calls and texts collected across an entire city or a large section of a country, using multiple antennas.

“It’s all automated, at the push of a button,” Nohl said. “It would strike me as a perfect spying capability, to record and decrypt pretty much any network… Any network we have tested, it works.”

Those tests have included more than 20 networks worldwide, including T-Mobile in the United States. The other major U.S. carriers have not been tested, though Nohl and Engel said it’s likely at least some of them have similar vulnerabilities. (Several smartphone-based text messaging systems, such as Apple’s iMessage and Whatsapp, use end-to-end encryption methods that sidestep traditional cellular text systems and likely would defeat the technique described by Nohl and Engel.)”

 
“In a statement, T-Mobile said: “T-Mobile remains vigilant in our work with other mobile operators, vendors and standards bodies to promote measures that can detect and prevent these attacks.”

The issue of cell phone interception is particularly sensitive in Germany because of news reports last year, based on documents provided by former NSA contractor Edward Snowden, that a phone belonging to Chancellor Angela Merkel was the subject of NSA surveillance. The techniques of that surveillance have not become public, though Nohl said that the SS7 hacking method that he and Engel discovered is one of several possibilities.

U.S. embassies and consulates in dozens of foreign cities, including Berlin, are outfitted with antennas for collecting cellular signals, according to reports by German magazine Der Spiegel, based on documents released by Snowden. Many cell phone conversations worldwide happen with either no encryption or weak encryption.

The move to 3G networks offers far better encryption and the prospect of private communications, but the hacking techniques revealed by Nohl and Engel undermine that possibility. Carriers can potentially guard their networks against efforts by hackers to collect encryption keys, but it’s unclear how many have done so. One network that operates in Germany, Vodafone, recently began blocking such requests after Nohl reported the problem to the company two weeks ago.

Nohl and Engel also have discovered new ways to track the locations of cell phone users through SS7. The Post story, in August, reported that several companies were offering governments worldwide the ability to find virtually any cell phone user, virtually anywhere in the world, by learning the location of their cell phones through an SS7 function called an “Any Time Interrogation” query.

Some carriers block such requests, and several began doing so after the Post’s report. But the researchers in recent months have found several other techniques that hackers could use to find the locations of callers by using different SS7 queries. All networks must track their customers in order to route calls to the nearest cellular towers, but they are not required to share that information with other networks or foreign governments.

Carriers everywhere must turn over location information and allow eavesdropping of calls when ordered to by government officials in whatever country they are operating in. But the techniques discovered by Nohl and Engel offer the possibility of much broader collection of caller locations and conversations, by anyone with access to SS7 and the required technical skills to send the appropriate queries.

“I doubt we are the first ones in the world who realize how open the SS7 network is,” Engel said.

Secretly eavesdropping on calls and texts would violate laws in many countries, including the United States, except when done with explicit court or other government authorization. Such restrictions likely do little to deter criminals or foreign spies, say surveillance experts, who say that embassies based in Washington likely collect cellular signals.

The researchers also found that it was possible to use SS7 to learn the phone numbers of people whose cellular signals are collected using surveillance devices. The calls transmit a temporary identification number which, by sending SS7 queries, can lead to the discovery of the phone number. That allows location tracking within a certain area, such as near government buildings.

The German senator who cooperated in Nohl’s demonstration of the technology, Thomas Jarzombek of Merkel’s Christian Democratic Union party, said that while many in that nation have been deeply angered by revelations about NSA spying, few are surprised that such intrusions are possible.

“After all the NSA and Snowden things we’ve heard, I guess nobody believes it’s possible to have a truly private conversation on a mobile phone,” he said. “When I really need a confidential conversation, I use a fixed-line” phone.”