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 AM •
Interesting research: “Who Can Find My Devices? Security and Privacy of Apple’s Crowd-Sourced Bluetooth Location Tracking System“:
Abstract: Overnight, Apple has turned its hundreds-of-million-device ecosystem into the world’s largest crowd-sourced location tracking network called offline finding (OF). OF leverages online finder devices to detect the presence of missing offline devices using Bluetooth and report an approximate location back to the owner via the Internet. While OF is not the first system of its kind, it is the first to commit to strong privacy goals. In particular, OF aims to ensure finder anonymity, untrackability of owner devices, and confidentiality of location reports. This paper presents the first comprehensive security and privacy analysis of OF. To this end, we recover the specifications of the closed-source OF protocols by means of reverse engineering. We experimentally show that unauthorized access to the location reports allows for accurate device tracking and retrieving a user’s top locations with an error in the order of 10 meters in urban areas. While we find that OF’s design achieves its privacy goals, we discover two distinct design and implementation flaws that can lead to a location correlation attack and unauthorized access to the location history of the past seven days, which could deanonymize users. Apple has partially addressed the issues following our responsible disclosure. Finally, we make our research artifacts publicly available.
There is also code available on GitHub, which allows arbitrary Bluetooth devices to be tracked via Apple’s Find My network.
Posted on March 15, 2021 at 6:16 AM •
Slate magazine was able to cleverly read the Ghislaine Maxwell deposition and reverse-engineer many of the redacted names.
We’ve long known that redacting is hard in the modern age, but most of the failures to date have been a result of not realizing that covering digital text with a black bar doesn’t always remove the text from the underlying digital file. As far as I know, this reverse-engineering technique is new.
EDITED TO ADD: A similar technique was used in 1991 to recover the Dead Sea Scrolls.
Posted on October 27, 2020 at 6:34 AM •
As expected, IoT devices are filled with vulnerabilities:
As a thought experiment, Martin Hron, a researcher at security company Avast, reverse engineered one of the older coffee makers to see what kinds of hacks he could do with it. After just a week of effort, the unqualified answer was: quite a lot. Specifically, he could trigger the coffee maker to turn on the burner, dispense water, spin the bean grinder, and display a ransom message, all while beeping repeatedly. Oh, and by the way, the only way to stop the chaos was to unplug the power cord.
In any event, Hron said the ransom attack is just the beginning of what an attacker could do. With more work, he believes, an attacker could program a coffee maker — and possibly other appliances made by Smarter — to attack the router, computers, or other devices connected to the same network. And the attacker could probably do it with no overt sign anything was amiss.
Posted on September 29, 2020 at 6:16 AM •
New research: “Security Analysis of the Democracy Live Online Voting System“:
Abstract: Democracy Live’s OmniBallot platform is a web-based system for blank ballot delivery, ballot marking, and (optionally) online voting. Three states — Delaware, West Virginia, and New Jersey — recently announced that they will allow certain voters to cast votes online using OmniBallot, but, despite the well established risks of Internet voting, the system has never been the subject of a public, independent security review.
EDITED TO ADD: This post has been translated into Portuguese.
Posted on June 9, 2020 at 6:26 AM •
Human Rights Watch has reverse engineered an app used by the Chinese police to conduct mass surveillance on Turkic Muslims in Xinjiang. The details are fascinating, and chilling.
Boing Boing post.
Posted on May 13, 2019 at 6:37 AM •
Last month, the NSA released Ghidra, a software reverse-engineering tool. Early reactions are uniformly positive.
Three news articles.
Posted on April 8, 2019 at 9:50 AM •
Interesting research: “Self-encrypting deception: weaknesses in the encryption of solid state drives (SSDs)“:
Abstract: We have analyzed the hardware full-disk encryption of several SSDs by reverse engineering their firmware. In theory, the security guarantees offered by hardware encryption are similar to or better than software implementations. In reality, we found that many hardware implementations have critical security weaknesses, for many models allowing for complete recovery of the data without knowledge of any secret. BitLocker, the encryption software built into Microsoft Windows will rely exclusively on hardware full-disk encryption if the SSD advertises supported for it. Thus, for these drives, data protected by BitLocker is also compromised. This challenges the view that hardware encryption is preferable over software encryption. We conclude that one should not rely solely on hardware encryption offered by SSDs.
EDITED TO ADD: The NSA is known to attack firmware of SSDs.
EDITED TO ADD (11/13): CERT advisory. And older research.
Posted on November 6, 2018 at 6:51 AM •
The Center for Democracy and Technology has a good summary of the current state of the DMCA’s chilling effects on security research.
To underline the nature of chilling effects on hacking and security research, CDT has worked to describe how tinkerers, hackers, and security researchers of all types both contribute to a baseline level of security in our digital environment and, in turn, are shaped themselves by this environment, most notably when things they do upset others and result in threats, potential lawsuits, and prosecution. We’ve published two reports (sponsored by the Hewlett Foundation and MacArthur Foundation) about needed reforms to the law and the myriad of ways that security research directly improves people’s lives. To get a more complete picture, we wanted to talk to security researchers themselves and gauge the forces that shape their work; essentially, we wanted to “take the pulse” of the security research community.
Today, we are releasing a third report in service of this effort: “Taking the Pulse of Hacking: A Risk Basis for Security Research.” We report findings after having interviewed a set of 20 security researchers and hackers — half academic and half non-academic — about what considerations they take into account when starting new projects or engaging in new work, as well as to what extent they or their colleagues have faced threats in the past that chilled their work. The results in our report show that a wide variety of constraints shape the work they do, from technical constraints to ethical boundaries to legal concerns, including the DMCA and especially the CFAA.
Note: I am a signatory on the letter supporting unrestricted security research.
Posted on April 16, 2018 at 6:46 AM •
Some details about the iPhone unlocker from the US company Greyshift, with photos.
Little is known about Grayshift or its sales model at this point. We don’t know whether sales are limited to US law enforcement, or if it is also selling in other parts of the world. Regardless of that, it’s highly likely that these devices will ultimately end up in the hands of agents of an oppressive regime, whether directly from Grayshift or indirectly through the black market.
It’s also entirely possible, based on the history of the IP-Box, that Grayshift devices will end up being available to anyone who wants them and can find a way to purchase them, perhaps by being reverse-engineered and reproduced by an enterprising hacker, then sold for a couple hundred bucks on eBay.
Forbes originally wrote about this, and I blogged that article.
Posted on March 23, 2018 at 6:28 AM •
Sidebar photo of Bruce Schneier by Joe MacInnis.