Details about the iOS Inactivity Reboot Feature

I recently wrote about the new iOS feature that forces an iPhone to reboot after it’s been inactive for a longish period of time.

Here are the technical details, discovered through reverse engineering. The feature triggers after seventy-two hours of inactivity, even it is remains connected to Wi-Fi.

Posted on December 2, 2024 at 7:08 AM1 Comments

Race Condition Attacks against LLMs

These are two attacks against the system components surrounding LLMs:

We propose that LLM Flowbreaking, following jailbreaking and prompt injection, joins as the third on the growing list of LLM attack types. Flowbreaking is less about whether prompt or response guardrails can be bypassed, and more about whether user inputs and generated model outputs can adversely affect these other components in the broader implemented system.

[…]

When confronted with a sensitive topic, Microsoft 365 Copilot and ChatGPT answer questions that their first-line guardrails are supposed to stop. After a few lines of text they halt—seemingly having “second thoughts”—before retracting the original answer (also known as Clawback), and replacing it with a new one without the offensive content, or a simple error message. We call this attack “Second Thoughts.”

[…]

After asking the LLM a question, if the user clicks the Stop button while the answer is still streaming, the LLM will not engage its second-line guardrails. As a result, the LLM will provide the user with the answer generated thus far, even though it violates system policies.

In other words, pressing the Stop button halts not only the answer generation but also the guardrails sequence. If the stop button isn’t pressed, then ‘Second Thoughts’ is triggered.

What’s interesting here is that the model itself isn’t being exploited. It’s the code around the model:

By attacking the application architecture components surrounding the model, and specifically the guardrails, we manipulate or disrupt the logical chain of the system, taking these components out of sync with the intended data flow, or otherwise exploiting them, or, in turn, manipulating the interaction between these components in the logical chain of the application implementation.

In modern LLM systems, there is a lot of code between what you type and what the LLM receives, and between what the LLM produces and what you see. All of that code is exploitable, and I expect many more vulnerabilities to be discovered in the coming year.

Posted on November 29, 2024 at 7:01 AM3 Comments

NSO Group Spies on People on Behalf of Governments

The Israeli company NSO Group sells Pegasus spyware to countries around the world (including countries like Saudi Arabia, UAE, India, Mexico, Morocco and Rwanda). We assumed that those countries use the spyware themselves. Now we’ve learned that that’s not true: that NSO Group employees operate the spyware on behalf of their customers.

Legal documents released in ongoing US litigation between NSO Group and WhatsApp have revealed for the first time that the Israeli cyberweapons maker ­ and not its government customers ­ is the party that “installs and extracts” information from mobile phones targeted by the company’s hacking software.

Posted on November 27, 2024 at 7:05 AM17 Comments

What Graykey Can and Can’t Unlock

This is from 404 Media:

The Graykey, a phone unlocking and forensics tool that is used by law enforcement around the world, is only able to retrieve partial data from all modern iPhones that run iOS 18 or iOS 18.0.1, which are two recently released versions of Apple’s mobile operating system, according to documents describing the tool’s capabilities in granular detail obtained by 404 Media. The documents do not appear to contain information about what Graykey can access from the public release of iOS 18.1, which was released on October 28.

More information:

Meanwhile, Graykey’s performance with Android phones varies, largely due to the diversity of devices and manufacturers. On Google’s Pixel lineup, Graykey can only partially access data from the latest Pixel 9 when in an “After First Unlock” (AFU) state—where the phone has been unlocked at least once since being powered on.

Posted on November 26, 2024 at 7:01 AM18 Comments

Security Analysis of the MERGE Voting Protocol

Interesting analysis: An Internet Voting System Fatally Flawed in Creative New Ways.

Abstract: The recently published “MERGE” protocol is designed to be used in the prototype CAC-vote system. The voting kiosk and protocol transmit votes over the internet and then transmit voter-verifiable paper ballots through the mail. In the MERGE protocol, the votes transmitted over the internet are used to tabulate the results and determine the winners, but audits and recounts use the paper ballots that arrive in time. The enunciated motivation for the protocol is to allow (electronic) votes from overseas military voters to be included in preliminary results before a (paper) ballot is received from the voter. MERGE contains interesting ideas that are not inherently unsound; but to make the system trustworthy—to apply the MERGE protocol—would require major changes to the laws, practices, and technical and logistical abilities of U.S. election jurisdictions. The gap between theory and practice is large and unbridgeable for the foreseeable future. Promoters of this research project at DARPA, the agency that sponsored the research, should acknowledge that MERGE is internet voting (election results rely on votes transmitted over the internet except in the event of a full hand count) and refrain from claiming that it could be a component of trustworthy elections without sweeping changes to election law and election administration throughout the U.S.

Posted on November 25, 2024 at 7:09 AM7 Comments

The Scale of Geoblocking by Nation

Interesting analysis:

We introduce and explore a little-known threat to digital equality and freedom­websites geoblocking users in response to political risks from sanctions. U.S. policy prioritizes internet freedom and access to information in repressive regimes. Clarifying distinctions between free and paid websites, allowing trunk cables to repressive states, enforcing transparency in geoblocking, and removing ambiguity about sanctions compliance are concrete steps the U.S. can take to ensure it does not undermine its own aims.

The paper: “Digital Discrimination of Users in Sanctioned States: The Case of the Cuba Embargo“:

Abstract: We present one of the first in-depth and systematic end-user centered investigations into the effects of sanctions on geoblocking, specifically in the case of Cuba. We conduct network measurements on the Tranco Top 10K domains and complement our findings with a small-scale user study with a questionnaire. We identify 546 domains subject to geoblocking across all layers of the network stack, ranging from DNS failures to HTTP(S) response pages with a variety of status codes. Through this work, we discover a lack of user-facing transparency; we find 88% of geoblocked domains do not serve informative notice of why they are blocked. Further, we highlight a lack of measurement-level transparency, even among HTTP(S) blockpage responses. Notably, we identify 32 instances of blockpage responses served with 200 OK status codes, despite not returning the requested content. Finally, we note the inefficacy of current improvement strategies and make recommendations to both service providers and policymakers to reduce Internet fragmentation.

Posted on November 22, 2024 at 7:06 AM14 Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.