This is a new vulnerability against Apple’s M1 chip. Researchers say that it is unpatchable.
Researchers from MIT’s Computer Science and Artificial Intelligence Laboratory, however, have created a novel hardware attack, which combines memory corruption and speculative execution attacks to sidestep the security feature. The attack shows that pointer authentication can be defeated without leaving a trace, and as it utilizes a hardware mechanism, no software patch can fix it.
The attack, appropriately called “Pacman,” works by “guessing” a pointer authentication code (PAC), a cryptographic signature that confirms that an app hasn’t been maliciously altered. This is done using speculative execution—a technique used by modern computer processors to speed up performance by speculatively guessing various lines of computation—to leak PAC verification results, while a hardware side-channel reveals whether or not the guess was correct.
What’s more, since there are only so many possible values for the PAC, the researchers found that it’s possible to try them all to find the right one.
It’s not obvious how to exploit this vulnerability in the wild, so I’m unsure how important this is. Also, I don’t know if it also applies to Apple’s new M2 chip.
Research paper. Another news article.
Posted on June 15, 2022 at 6:05 AM •
Apple Mail now blocks email trackers by default.
Most email newsletters you get include an invisible “image,” typically a single white pixel, with a unique file name. The server keeps track of every time this “image” is opened and by which IP address. This quirk of internet history means that marketers can track exactly when you open an email and your IP address, which can be used to roughly work out your location.
So, how does Apple Mail stop this? By caching. Apple Mail downloads all images for all emails before you open them. Practically speaking, that means every message downloaded to Apple Mail is marked “read,” regardless of whether you open it. Apples also routes the download through two different proxies, meaning your precise location also can’t be tracked.
Crypto-Gram uses Mailchimp, which has these tracking pixels turned on by default. I turn them off. Normally, Mailchimp requires them to be left on for the first few mailings, presumably to prevent abuse. The company waived that requirement for me.
Posted on May 9, 2022 at 9:39 AM •
Ever since Apple introduced AirTags, security people have warned that they could be used for stalking. But while there have been a bunch of anecdotal stories, this is the first vaguely scientific survey:
Motherboard requested records mentioning AirTags in a recent eight month period from dozens of the country’s largest police departments. We obtained records from eight police departments.
Of the 150 total police reports mentioning AirTags, in 50 cases women called the police because they started getting notifications that their whereabouts were being tracked by an AirTag they didn’t own. Of those, 25 could identify a man in their lives—ex-partners, husbands, bosses—who they strongly suspected planted the AirTags on their cars in order to follow and harass them. Those women reported that current and former intimate partners—the most likely people to harm women overall—are using AirTags to stalk and harass them.
Eight police departments over eight months yielded fifty cases. And that’s only where the victim (1) realized they were being tracked by someone else’s AirTag, and (2) contacted the police. That’s going to multiply out to a lot of AirTag stalking in the country, and the world.
EDITED TO ADD (4/13): AirTags are being used by Ukrainians to track goods stolen by Russians and, as a nice side effect, to track the movements of Russian troops.
Posted on April 8, 2022 at 6:06 AM •
The malicious uses of these technologies are scary:
Police reportedly arrived on the scene last week and found the man crouched beside the woman’s passenger side door. According to the police, the man had, at some point, wrapped his Apple Watch across the spokes of the woman’s passenger side front car wheel and then used the Watch to track her movements. When police eventually confronted him, he admitted the Watch was his. Now, he’s reportedly being charged with attaching an electronic tracking device to the woman’s vehicle.
Posted on March 30, 2022 at 6:29 AM •
A Berlin-based company has developed an AirTag clone that bypasses Apple’s anti-stalker security systems. Source code for these AirTag clones is available online.
So now we have several problems with the system. Apple’s anti-stalker security only works with iPhones. (Apple wrote an Android app that can detect AirTags, but how many people are going to download it?) And now non-AirTags can piggyback on Apple’s system without triggering the alarms.
Apple didn’t think this through nearly as well as it claims to have. I think the general problem is one that I have written about before: designers just don’t have intimate threats in mind when building these systems.
Posted on February 23, 2022 at 6:28 AM •
There are two bills working their way through Congress that would force companies like Apple to allow competitive app stores. Apple hates this, since it would break its monopoly, and it’s making a variety of security arguments to bolster its argument. I have written a rebuttal:
I would like to address some of the unfounded security concerns raised about these bills. It’s simply not true that this legislation puts user privacy and security at risk. In fact, it’s fairer to say that this legislation puts those companies’ extractive business-models at risk. Their claims about risks to privacy and security are both false and disingenuous, and motivated by their own self-interest and not the public interest. App store monopolies cannot protect users from every risk, and they frequently prevent the distribution of important tools that actually enhance security. Furthermore, the alleged risks of third-party app stores and “side-loading” apps pale in comparison to their benefits. These bills will encourage competition, prevent monopolist extortion, and guarantee users a new right to digital self-determination.
Matt Stoller has also written about this.
EDITED TO ADD (2/13): Here are the two bills.
Posted on February 1, 2022 at 2:26 PM •
A German activist is trying to track down a secret government intelligence agency. One of her research techniques is to mail Apple AirTags to see where they actually end up:
Wittmann says that everyone she spoke to denied being part of this intelligence agency. But what she describes as a “good indicator,” would be if she could prove that the postal address for this “federal authority” actually leads to the intelligence service’s apparent offices.
“To understand where mail ends up,” she writes (in translation), “[you can do] a lot of manual research. Or you can simply send a small device that regularly transmits its current position (a so-called AirTag) and see where it lands.”
She sent a parcel with an AirTag and watched through Apple’s Find My system as it was delivered via the Berlin sorting center to a sorting office in Cologne-Ehrenfeld. And then appears at the Office for the Protection of the Constitution in Cologne.
So an AirTag addressed to a telecommunications authority based in one part of Germany, ends up in the offices of an intelligence agency based in another part of the country.
Wittmann’s research is also now detailed in the German Wikipedia entry for the federal telecommunications service. It recounts how following her original discovery in December 2021, subsequent government press conferences have denied that there is such a federal telecommunications service at all.
Here’s the original Medium post, in German.
In a similar story, someone used an AirTag to track her furniture as a moving company lied about its whereabouts.
EDITED TO ADD (2/13): Another AirTag tracking story.
Posted on January 28, 2022 at 6:13 AM •
Researchers have figured how how to intercept and fake an iPhone reboot:
We’ll dissect the iOS system and show how it’s possible to alter a shutdown event, tricking a user that got infected into thinking that the phone has been powered off, but in fact, it’s still running. The “NoReboot” approach simulates a real shutdown. The user cannot feel a difference between a real shutdown and a “fake shutdown.” There is no user-interface or any button feedback until the user turns the phone back “on.”
It’s a complicated hack, but it works.
Uses are obvious:
Historically, when malware infects an iOS device, it can be removed simply by restarting the device, which clears the malware from memory.
However, this technique hooks the shutdown and reboot routines to prevent them from ever happening, allowing malware to achieve persistence as the device is never actually turned off.
I see this as another manifestation of the security problems that stem from all controls becoming software controls. Back when the physical buttons actually did things—like turn the power, the Wi-Fi, or the camera on and off—you could actually know that something was on or off. Now that software controls those functions, you can never be sure.
Posted on January 12, 2022 at 6:15 AM •
Some European cell phone carriers, and now T-Mobile, are blocking Apple’s Private Relay anonymous browsing feature.
This could be an interesting battle to watch.
Posted on January 11, 2022 at 9:09 AM •
This development suprises no one who has been paying attention:
Researchers now believe AirTags, which are equipped with Bluetooth technology, could be revealing a more widespread problem of tech-enabled tracking. They emit a digital signal that can be detected by devices running Apple’s mobile operating system. Those devices then report where an AirTag has last been seen. Unlike similar tracking products from competitors such as Tile, Apple added features to prevent abuse, including notifications like the one Ms. Estrada received and automatic beeping. (Tile plans to release a feature to prevent the tracking of people next year, a spokeswoman for that company said.)
A person who doesn’t own an iPhone might have a harder time detecting an unwanted AirTag. AirTags aren’t compatible with Android smartphones. Earlier this month, Apple released an Android app that can scan for AirTags—but you have to be vigilant enough to download it and proactively use it.
Apple declined to say if it was working with Google on technology that would allow Android phones to automatically detect its trackers.
People who said they have been tracked have called Apple’s safeguards insufficient. Ms. Estrada said she was notified four hours after her phone first noticed the rogue gadget. Others said it took days before they were made aware of an unknown AirTag. According to Apple, the timing of the alerts can vary depending on the iPhone’s operating system and location settings.
Posted on December 31, 2021 at 9:52 AM •
Sidebar photo of Bruce Schneier by Joe MacInnis.