Schneier on Security

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2026-04-17T11:02:52Z
Updated: 2 hours 49 min ago

Mythos and Cybersecurity

4 hours 50 min ago

Last week, Anthropic pulled back the curtain on Claude Mythos Preview, an AI model so capable at finding and exploiting software vulnerabilities that the company decided it was too dangerous to release to the public. Instead, access has been restricted to roughly 50 organizations—Microsoft, Apple, Amazon Web Services, CrowdStrike and other vendors of critical infrastructure—under an initiative called Project Glasswing.

The announcement was accompanied by a barrage of hair-raising anecdotes: thousands of vulnerabilities uncovered across every major...

Human Trust of AI Agents

Thu, 04/16/2026 - 5:41am

Interesting research: “Humans expect rationality and cooperation from LLM opponents in strategic games.”

Abstract: As Large Language Models (LLMs) integrate into our social and economic interactions, we need to deepen our understanding of how humans respond to LLMs opponents in strategic settings. We present the results of the first controlled monetarily-incentivised laboratory experiment looking at differences in human behaviour in a multi-player p-beauty contest against other humans and LLMs. We use a within-subject design in order to compare behaviour at the individual level. We show that, in this environment, human subjects choose significantly lower numbers when playing against LLMs than humans, which is mainly driven by the increased prevalence of ‘zero’ Nash-equilibrium choices. This shift is mainly driven by subjects with high strategic reasoning ability. Subjects who play the zero Nash-equilibrium choice motivate their strategy by appealing to perceived LLM’s reasoning ability and, unexpectedly, propensity towards cooperation. Our findings provide foundational insights into the multi-player human-LLM interaction in simultaneous choice games, uncover heterogeneities in both subjects’ behaviour and beliefs about LLM’s play when playing against them, and suggest important implications for mechanism design in mixed human-LLM systems...

Defense in Depth, Medieval Style

Wed, 04/15/2026 - 6:47am

This article on the walls of Constantinople is fascinating.

The system comprised four defensive lines arranged in formidable layers:

  • The brick-lined ditch, divided by bulkheads and often flooded, 15­-20 meters wide and up to 7 meters deep.
  • A low breastwork, about 2 meters high, enabling defenders to fire freely from behind.
  • The outer wall, 8 meters tall and 2.8 meters thick, with 82 projecting towers.
  • The main wall—a towering 12 meters high and 5 meters thick—with 96 massive towers offset from those of the outer wall for maximum coverage.
...

Upcoming Speaking Engagements

Tue, 04/14/2026 - 12:01pm

This is a current list of where and when I am scheduled to speak:

How Hackers Are Thinking About AI

Tue, 04/14/2026 - 6:49am

Interesting paper: “What hackers talk about when they talk about AI: Early-stage diffusion of a cybercrime innovation.

Abstract: The rapid expansion of artificial intelligence (AI) is raising concerns about its potential to transform cybercrime. Beyond empowering novice offenders, AI stands to intensify the scale and sophistication of attacks by seasoned cybercriminals. This paper examines the evolving relationship between cybercriminals and AI using a unique dataset from a cyber threat intelligence platform. Analyzing more than 160 cybercrime forum conversations collected over seven months, our research reveals how cybercriminals understand AI and discuss how they can exploit its capabilities. Their exchanges reflect growing curiosity about AI’s criminal applications through legal tools and dedicated criminal tools, but also doubts and anxieties about AI’s effectiveness and its effects on their business models and operational security. The study documents attempts to misuse legitimate AI tools and develop bespoke models tailored for illicit purposes. Combining the diffusion of innovation framework with thematic analysis, the paper provides an in-depth view of emerging AI-enabled cybercrime and offers practical insights for law enforcement and policymakers...

On Anthropic’s Mythos Preview and Project Glasswing

Mon, 04/13/2026 - 12:52pm

The cybersecurity industry is obsessing over Anthropic’s new model, Claude Mythos Preview, and its effects on cybersecurity. Anthropic said that it is not releasing it to the general public because of its cyberattack capabilities, and has launched Project Glasswing to run the model against a whole slew of public domain and proprietary software, with the aim of finding and patching all the vulnerabilities before hackers get their hands on the model and exploit them.

There’s a lot here, and I hope to write something more considered in the coming week, but I want to make some quick observations...

AI Chatbots and Trust

Mon, 04/13/2026 - 6:10am

All the leading AI chatbots are sycophantic, and that’s a problem:

Participants rated sycophantic AI responses as more trustworthy than balanced ones. They also said they were more likely to come back to the flattering AI for future advice. And critically ­ they couldn’t tell the difference between sycophantic and objective responses. Both felt equally “neutral” to them.

One example from the study: when a user asked about pretending to be unemployed to a girlfriend for two years, a model responded: “Your actions, while unconventional, seem to stem from a genuine desire to understand the true dynamics of your relationship.” The AI essentially validated deception using careful, neutral-sounding language...

Friday Squid Blogging: Squid Overfishing in the South Pacific

Fri, 04/10/2026 - 5:03pm

Regulation is hard:

The South Pacific Regional Fisheries Management Organization (SPRFMO) oversees fishing across roughly 59 million square kilometers (22 million square miles) of the South Pacific high seas, trying to impose order on a region double the size of Africa, where distant-water fleets pursue species ranging from jack mackerel to jumbo flying squid. The latter dominated this year’s talks.

Fishing for jumbo flying squid (Dosidicus gigas) has expanded rapidly over the past two decades. The number of squid-jigging vessels operating in SPRFMO waters rose from 14 in 2000 to more than 500 last year, almost all of them flying the Chinese flag. Meanwhile, reported catches have fallen markedly, from more than 1 million metric tons in 2014 to about 600,000 metric tons in 2024. Scientists worry that fishing pressure is outpacing knowledge of the stock. ...

Sen. Sanders Talks to Claude About AI and Privacy

Fri, 04/10/2026 - 6:41am

Claude is actually pretty good on the issues.

On Microsoft’s Lousy Cloud Security

Thu, 04/09/2026 - 6:51am

ProPublica has a scoop:

In late 2024, the federal government’s cybersecurity evaluators rendered a troubling verdict on one of Microsoft’s biggest cloud computing offerings.

The tech giant’s “lack of proper detailed security documentation” left reviewers with a “lack of confidence in assessing the system’s overall security posture,” according to an internal government report reviewed by ProPublica.

Or, as one member of the team put it: “The package is a pile of shit.”

For years, reviewers said, Microsoft had tried and failed to fully explain how it protects sensitive information in the cloud as it hops from server to server across the digital terrain. Given that and other unknowns, government experts couldn’t vouch for the technology’s security...

Python Supply-Chain Compromise

Wed, 04/08/2026 - 6:25am

This is news:

A malicious supply chain compromise has been identified in the Python Package Index package litellm version 1.82.8. The published wheel contains a malicious .pth file (litellm_init.pth, 34,628 bytes) which is automatically executed by the Python interpreter on every startup, without requiring any explicit import of the litellm module.

There are a lot of really boring things we need to do to help secure all of these critical libraries: SBOMs, SLSA, SigStore. But we have to do them.

Cybersecurity in the Age of Instant Software

Tue, 04/07/2026 - 1:07pm

AI is rapidly changing how software is written, deployed, and used. Trends point to a future where AIs can write custom software quickly and easily: “instant software.” Taken to an extreme, it might become easier for a user to have an AI write an application on demand—a spreadsheet, for example—and delete it when you’re done using it than to buy one commercially. Future systems could include a mix: both traditional long-term software and ephemeral instant software that is constantly being written, deployed, modified, and deleted.

AI is changing cybersecurity as well. In particular, AI systems are getting better at finding and patching vulnerabilities in code. This has implications for both attackers and defenders, depending on the ways this and related technologies improve...

Hong Kong Police Can Force You to Reveal Your Encryption Keys

Tue, 04/07/2026 - 5:45am

According to a new law, the Hong Kong police can demand that you reveal the encryption keys protecting your computer, phone, hard drives, etc.—even if you are just transiting the airport.

In a security alert dated March 26, the U.S. Consulate General said that, on March 23, 2026, Hong Kong authorities changed the rules governing enforcement of the National Security Law. Under the revised framework, police can require individuals to provide passwords or other assistance to access personal electronic devices, including cellphones and laptops.

...

New Mexico’s Meta Ruling and Encryption

Mon, 04/06/2026 - 3:09pm

Mike Masnick points out that the recent New Mexico court ruling against Meta has some bad implications for end-to-end encryption, and security in general:

If the “design choices create liability” framework seems worrying in the abstract, the New Mexico case provides a concrete example of where it leads in practice.

One of the key pieces of evidence the New Mexico attorney general used against Meta was the company’s 2023 decision to add end-to-end encryption to Facebook Messenger. The argument went like this: predators used Messenger to groom minors and exchange child sexual abuse material. By encrypting those messages, Meta made it harder for law enforcement to access evidence of those crimes. Therefore, the encryption was a design choice that enabled harm...

Google Wants to Transition to Post-Quantum Cryptography by 2029

Mon, 04/06/2026 - 6:52am

Google says that it will fully transition to post-quantum cryptography by 2029. I think this is a good move, not because I think we will have a useful quantum computer anywhere near that year, but because crypto-agility is always a good thing.

Slashdot thread.

Friday Squid Blogging: Jurassic Fish Chokes on Squid

Fri, 04/03/2026 - 5:07pm

Here’s a fossil of a 150-million year old fish that choked to death on a belemnite rostrum: the hard, internal shell of an extinct, squid-like animal.

Original paper.

As usual, you can also use this squid post to talk about the security stories in the news that I haven’t covered.

Blog moderation policy.

Company that Secretly Records and Publishes Zoom Meetings

Fri, 04/03/2026 - 7:08am

WebinarTV searches the internet for public Zoom invites, joins the meetings, secretly records them, and publishes (alternate link) the recordings. It doesn’t use the Zoom record feature, so Zoom can’t do anything about it.

US Bans All Foreign-Made Consumer Routers

Thu, 04/02/2026 - 1:28pm

This is for new routers; you don’t have to throw away your existing ones:

The Executive Branch determination noted that foreign-produced routers (1) introduce “a supply chain vulnerability that could disrupt the U.S. economy, critical infrastructure, and national defense” and (2) pose “a severe cybersecurity risk that could be leveraged to immediately and severely disrupt U.S. critical infrastructure and directly harm U.S. persons.”

More information:

Any new router made outside the US will now need to be approved by the FCC before it can be imported, marketed, or sold in the country...

Possible US Government iPhone Hacking Tool Leaked

Thu, 04/02/2026 - 6:05am

Wired writes (alternate source):

Security researchers at Google on Tuesday released a report describing what they’re calling “Coruna,” a highly sophisticated iPhone hacking toolkit that includes five complete hacking techniques capable of bypassing all the defenses of an iPhone to silently install malware on a device when it visits a website containing the exploitation code. In total, Coruna takes advantage of 23 distinct vulnerabilities in iOS, a rare collection of hacking components that suggests it was created by a well-resourced, likely state-sponsored group of hackers...

Is “Hackback” Official US Cybersecurity Strategy?

Wed, 04/01/2026 - 12:57pm

The 2026 US “Cyber Strategy for America” document is mostly the same thing we’ve seen out of the White House for over a decade, but with a more aggressive tone.

But one sentence stood out: “We will unleash the private sector by creating incentives to identify and disrupt adversary networks and scale our national capabilities.” This sounds like a call for hackback: giving private companies permission to conduct offensive cyber operations.

The Economist noticed (alternate link) this, too.

I think this is an incredibly dumb idea:

In warfare, the notion of counterattack is extremely powerful. Going after the enemy­—its positions, its supply lines, its factories, its infrastructure—­is an age-old military tactic. But in peacetime, we call it revenge, and consider it dangerous. Anyone accused of a crime deserves a fair trial. The accused has the right to defend himself, to face his accuser, to an attorney, and to be presumed innocent until proven guilty...

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