Entries Tagged "iPhone"

Page 2 of 11

Apple’s NeuralHash Algorithm Has Been Reverse-Engineered

Apple’s NeuralHash algorithm—the one it’s using for client-side scanning on the iPhone—has been reverse-engineered.

Turns out it was already in iOS 14.3, and someone noticed:

Early tests show that it can tolerate image resizing and compression, but not cropping or rotations.

We also have the first collision: two images that hash to the same value.

The next step is to generate innocuous images that NeuralHash classifies as prohibited content.

This was a bad idea from the start, and Apple never seemed to consider the adversarial context of the system as a whole, and not just the cryptography.

Posted on August 18, 2021 at 11:51 AMView Comments

Details on the Unlocking of the San Bernardino Terrorist’s iPhone

The Washington Post has published a long story on the unlocking of the San Bernardino Terrorist’s iPhone 5C in 2016. We all thought it was an Israeli company called Cellebrite. It was actually an Australian company called Azimuth Security.

Azimuth specialized in finding significant vulnerabilities. Dowd, a former IBM X-Force researcher whom one peer called “the Mozart of exploit design,” had found one in open-source code from Mozilla that Apple used to permit accessories to be plugged into an iPhone’s lightning port, according to the person.

[…]

Using the flaw Dowd found, Wang, based in Portland, Ore., created an exploit that enabled initial access to the phone ­ a foot in the door. Then he hitched it to another exploit that permitted greater maneuverability, according to the people. And then he linked that to a final exploit that another Azimuth researcher had already created for iPhones, giving him full control over the phone’s core processor ­ the brains of the device. From there, he wrote software that rapidly tried all combinations of the passcode, bypassing other features, such as the one that erased data after 10 incorrect tries.

Apple is suing various companies over this sort of thing. The article goes into the details.

Posted on April 19, 2021 at 6:08 AMView Comments

New iMessage Security Features

Apple has added added security features to mitigate the risk of zero-click iMessage attacks.

Apple did not document the changes but Groß said he fiddled around with the newest iOS 14 and found that Apple shipped a “significant refactoring of iMessage processing” that severely cripples the usual ways exploits are chained together for zero-click attacks.

Groß notes that memory corruption based zero-click exploits typically require exploitation of multiple vulnerabilities to create exploit chains. In most observed attacks, these could include a memory corruption vulnerability, reachable without user interaction and ideally without triggering any user notifications; a way to break ASLR remotely; a way to turn the vulnerability into remote code execution;; and a way to break out of any sandbox, typically by exploiting a separate vulnerability in another operating system component (e.g. a userspace service or the kernel).

Posted on January 29, 2021 at 9:20 AMView Comments

Impressive iPhone Exploit

This is a scarily impressive vulnerability:

Earlier this year, Apple patched one of the most breathtaking iPhone vulnerabilities ever: a memory corruption bug in the iOS kernel that gave attackers remote access to the entire device­—over Wi-Fi, with no user interaction required at all. Oh, and exploits were wormable­—meaning radio-proximity exploits could spread from one nearby device to another, once again, with no user interaction needed.

[…]

Beer’s attack worked by exploiting a buffer overflow bug in a driver for AWDL, an Apple-proprietary mesh networking protocol that makes things like Airdrop work. Because drivers reside in the kernel—­one of the most privileged parts of any operating system­—the AWDL flaw had the potential for serious hacks. And because AWDL parses Wi-Fi packets, exploits can be transmitted over the air, with no indication that anything is amiss.

[…]

Beer developed several different exploits. The most advanced one installs an implant that has full access to the user’s personal data, including emails, photos, messages, and passwords and crypto keys stored in the keychain. The attack uses a laptop, a Raspberry Pi, and some off-the-shelf Wi-Fi adapters. It takes about two minutes to install the prototype implant, but Beer said that with more work a better written exploit could deliver it in a “handful of seconds.” Exploits work only on devices that are within Wi-Fi range of the attacker.

There is no evidence that this vulnerability was ever used in the wild.

EDITED TO ADD: Slashdot thread.

Posted on December 2, 2020 at 1:55 PMView Comments

New Bluetooth Vulnerability

There’s a new unpatched Bluetooth vulnerability:

The issue is with a protocol called Cross-Transport Key Derivation (or CTKD, for short). When, say, an iPhone is getting ready to pair up with Bluetooth-powered device, CTKD’s role is to set up two separate authentication keys for that phone: one for a “Bluetooth Low Energy” device, and one for a device using what’s known as the “Basic Rate/Enhanced Data Rate” standard. Different devices require different amounts of data—and battery power—from a phone. Being able to toggle between the standards needed for Bluetooth devices that take a ton of data (like a Chromecast), and those that require a bit less (like a smartwatch) is more efficient. Incidentally, it might also be less secure.

According to the researchers, if a phone supports both of those standards but doesn’t require some sort of authentication or permission on the user’s end, a hackery sort who’s within Bluetooth range can use its CTKD connection to derive its own competing key. With that connection, according to the researchers, this sort of erzatz authentication can also allow bad actors to weaken the encryption that these keys use in the first place—which can open its owner up to more attacks further down the road, or perform “man in the middle” style attacks that snoop on unprotected data being sent by the phone’s apps and services.

Another article:

Patches are not immediately available at the time of writing. The only way to protect against BLURtooth attacks is to control the environment in which Bluetooth devices are paired, in order to prevent man-in-the-middle attacks, or pairings with rogue devices carried out via social engineering (tricking the human operator).

However, patches are expected to be available at one point. When they’ll be, they’ll most likely be integrated as firmware or operating system updates for Bluetooth capable devices.

The timeline for these updates is, for the moment, unclear, as device vendors and OS makers usually work on different timelines, and some may not prioritize security patches as others. The number of vulnerable devices is also unclear and hard to quantify.

Many Bluetooth devices can’t be patched.

Final note: this seems to be another example of simultaneous discovery:

According to the Bluetooth SIG, the BLURtooth attack was discovered independently by two groups of academics from the École Polytechnique Fédérale de Lausanne (EPFL) and Purdue University.

Posted on September 17, 2020 at 6:18 AMView Comments

New iPhone Zero-Day Discovered

Last year, ZecOps discovered two iPhone zero-day exploits. They will be patched in the next iOS release:

Avraham declined to disclose many details about who the targets were, and did not say whether they lost any data as a result of the attacks, but said “we were a bit surprised about who was targeted.” He said some of the targets were an executive from a telephone carrier in Japan, a “VIP” from Germany, managed security service providers from Saudi Arabia and Israel, people who work for a Fortune 500 company in North America, and an executive from a Swiss company.

[…]

On the other hand, this is not as polished a hack as others, as it relies on sending an oversized email, which may get blocked by certain email providers. Moreover, Avraham said it only works on the default Apple Mail app, and not on Gmail or Outlook, for example.

Posted on April 22, 2020 at 9:12 AMView Comments

Hacking Voice Assistants with Ultrasonic Waves

I previously wrote about hacking voice assistants with lasers. Turns you can do much the same thing with ultrasonic waves:

Voice assistants—the demo targeted Siri, Google Assistant, and Bixby—are designed to respond when they detect the owner’s voice after noticing a trigger phrase such as ‘Ok, Google’.

Ultimately, commands are just sound waves, which other researchers have already shown can be emulated using ultrasonic waves which humans can’t hear, providing an attacker has a line of sight on the device and the distance is short.

What SurfingAttack adds to this is the ability to send the ultrasonic commands through a solid glass or wood table on which the smartphone was sitting using a circular piezoelectric disc connected to its underside.

Although the distance was only 43cm (17 inches), hiding the disc under a surface represents a more plausible, easier-to-conceal attack method than previous techniques.

Research paper. Demonstration video.

Posted on March 23, 2020 at 6:19 AMView Comments

New Unpatchable iPhone Exploit Allows Jailbreaking

A new iOS exploit allows jailbreaking of pretty much all version of the iPhone. This is a huge deal for Apple, but at least it doesn’t allow someone to remotely hack people’s phones.

Some details:

I wanted to learn how Checkm8 will shape the iPhone experience­—particularly as it relates to security­—so I spoke at length with axi0mX on Friday. Thomas Reed, director of Mac offerings at security firm Malwarebytes, joined me. The takeaways from the long-ranging interview are:

  • Checkm8 requires physical access to the phone. It can’t be remotely executed, even if combined with other exploits.
  • The exploit allows only tethered jailbreaks, meaning it lacks persistence. The exploit must be run each time an iDevice boots.
  • Checkm8 doesn’t bypass the protections offered by the Secure Enclave and Touch ID.
  • All of the above means people will be able to use Checkm8 to install malware only under very limited circumstances. The above also means that Checkm8 is unlikely to make it easier for people who find, steal or confiscate a vulnerable iPhone, but don’t have the unlock PIN, to access the data stored on it.
  • Checkm8 is going to benefit researchers, hobbyists, and hackers by providing a way not seen in almost a decade to access the lowest levels of iDevices.

Also:

“The main people who are likely to benefit from this are security researchers, who are using their own phone in controlled conditions. This process allows them to gain more control over the phone and so improves visibility into research on iOS or other apps on the phone,” Wood says. “For normal users, this is unlikely to have any effect, there are too many extra hurdles currently in place that they would have to get over to do anything significant.”

If a regular person with no prior knowledge of jailbreaking wanted to use this exploit to jailbreak their iPhone, they would find it extremely difficult, simply because Checkm8 just gives you access to the exploit, but not a jailbreak in itself. It’s also a ‘tethered exploit’, meaning that the jailbreak can only be triggered when connected to a computer via USB and will become untethered once the device restarts.

Posted on October 8, 2019 at 5:24 AMView Comments

Massive iPhone Hack Targets Uyghurs

China is being blamed for a massive surveillance operation that targeted Uyghur Muslims. This story broke in waves, the first wave being about the iPhone.

Earlier this year, Google’s Project Zero found a series of websites that have been using zero-day vulnerabilities to indiscriminately install malware on iPhones that would visit the site. (The vulnerabilities were patched in iOS 12.1.4, released on February 7.)

Earlier this year Google’s Threat Analysis Group (TAG) discovered a small collection of hacked websites. The hacked sites were being used in indiscriminate watering hole attacks against their visitors, using iPhone 0-day.

There was no target discrimination; simply visiting the hacked site was enough for the exploit server to attack your device, and if it was successful, install a monitoring implant. We estimate that these sites receive thousands of visitors per week.

TAG was able to collect five separate, complete and unique iPhone exploit chains, covering almost every version from iOS 10 through to the latest version of iOS 12. This indicated a group making a sustained effort to hack the users of iPhones in certain communities over a period of at least two years.

Four more news stories.

This upends pretty much everything we know about iPhone hacking. We believed that it was hard. We believed that effective zero-day exploits cost $2M or $3M, and were used sparingly by governments only against high-value targets. We believed that if an exploit was used too frequently, it would be quickly discovered and patched.

None of that is true here. This operation used fourteen zero-days exploits. It used them indiscriminately. And it remained undetected for two years. (I waited before posting this because I wanted to see if someone would rebut this story, or explain it somehow.)

Google’s announcement left out of details, like the URLs of the sites delivering the malware. That omission meant that we had no idea who was behind the attack, although the speculation was that it was a nation-state.

Subsequent reporting added that malware against Android phones and the Windows operating system were also delivered by those websites. And then that the websites were targeted at Uyghurs. Which leads us all to blame China.

So now this is a story of a large, expensive, indiscriminate, Chinese-run surveillance operation against an ethnic minority in their country. And the politics will overshadow the tech. But the tech is still really impressive.

EDITED TO ADD: New data on the value of smartphone exploits:

According to the company, starting today, a zero-click (no user interaction) exploit chain for Android can get hackers and security researchers up to $2.5 million in rewards. A similar exploit chain impacting iOS is worth only $2 million.

EDITED TO ADD (9/6): Apple disputes some of the claims Google made about the extent of the vulnerabilities and the attack.

EDITED TO ADD (9/7): More on Apple’s pushbacks.

Posted on September 3, 2019 at 6:09 AMView Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.