Threat Modeling MCP Server

A Model Context Protocol (MCP) server for comprehensive threat modeling with automatic code validation

This server provides tools for threat modeling, including business context analysis, architecture analysis, threat actor analysis, trust boundary analysis, asset flow analysis, code security validation and comprehensive report generation. — Read More

#cyber

Measuring LLMs’ ability to develop exploits

Claude Mythos Preview’s ability to develop exploits is a step-change over previous frontier models. This was one of our primary motivations for rolling out the model carefully through Project Glasswing rather than through a general release. Mythos Preview is capable of finding complex vulnerabilities, but what concerned us most in our internal testing was that Mythos Preview could both turn vulnerabilities into exploit primitives, and combine those primitives together into complete end-to-end attack chains.

When we published our Mythos Preview results, we measured its capabilities by having it search for novel zero-days and then build exploits for them. Qualitative evaluations like this are helpful for showcasing a model’s capabilities—but ideally, we would have high-quality quantitative benchmarks that let us measure them precisely. The problem we faced at the time we released Mythos Preview was that no existing public exploit benchmarks were difficult enough to capture Mythos Preview’s capabilities in our initial testing. — Read More

#cyber

Cisco: AI traffic is radically reshaping WANs

… Cisco’s new study, AI Impact on Wide Area Networks 2026, finds AI and agentic AI will not only increase traffic volume but also, “they will change traffic shape, symmetry, duration, and criticality,” the study reports. “AI inference paths will become strategic network assets, requiring high levels of resilience, observability, and differentiated treatment, for example, Quality of Service (QoS) and path security.” — Read More

#cyber

NO SECURITY METER FOR AI

Let’s say you wanted to make sure that your AI is secure. Can you just maximize the security and privacy benchmark
and call it a day? Nope, because benchmarks don’t actually work for measuring AI capabilities (even when they are
NOT emergent systemic properties like security). So let’s take a step back: how do you measure security in the first
place? Good question. Over the last 30 years, security engineering for software evolved from black box penetration testing, through whitebox code analysis and architectural risk analysis to de facto process-driven standards like
the Building Security In Maturity Model (BSIMM). Software had a very deep impact on business operations, and it
appears that AI is going to have an even deeper impact. Will a software security-like measurement move work for
AI? Probably. In the meantime we can make real progress in AI security by cleaning up our WHAT piles and managing risk by identifying and applying good assurance processes. (Spoiler alert: no matter what we do, we still don’t
get a security meter for AI, so we need to be extra vigilant about security.) — Read More

#cyber

Mythos for Offensive Security: XBOW’s Evaluation

About two months ago, Anthropic invited us to help them assess the capability of a new model they thought represented a significant shift in capability. So we put it through our security gauntlet. Benchmarks, workflows, interactive use, and integrations.

Today, we can finally share details on how we tested Mythos Preview, what we found, and what it means. 

Spoilers: This model is a major advance. It is substantially better than prior models at finding vulnerability candidates, especially when source code is available. It communicates with unusual technical precision, reasons well about code, and shows strong promise in complex domains such as native-code analysis and reverse engineering. 

Our takeaway: Mythos Preview is a powerful tool for generating strong vulnerability leads and technically precise analysis. It is especially adept at analyzing source code with a security mindset. It’s not magic, though: a model is a brain without a body. While source code audits are mostly a brain activity, live site pentests like the ones XBOW performs very much need a body whose skill and control can match the brain’s power. — Read More

#cyber

Defense at AI speed: Microsoft’s new multi-model agentic security system tops leading industry benchmark

Today Microsoft announced a major step forward in AI-powered cyber defense: our new agentic security system helped researchers find 16 new vulnerabilities across the Windows networking and authentication stack—including four Critical remote code execution flaws in components such as the Windows kernel TCP/IP stack and the IKEv2 service. They used the new Microsoft Security multi-model agentic scanning harness (codename MDASH) which was built by Microsoft’s Autonomous Code Security team. Unlike single-model approaches, the harness orchestrates more than 100 specialized AI agents across an ensemble of frontier and distilled models to discover, debate, and prove exploitable bugs end-to-end.

The results speak for themselves: 21 of 21 planted vulnerabilities found with zero false positives on a private test driver; 96% recall against five years of confirmed Microsoft Security Response Center (MSRC) cases in clfs.sys and 100% in tcpip.sys; and an industry-leading 88.45% score on the public CyberGym benchmark of 1,507 real-world vulnerabilities—the top score on the leaderboard, roughly five points ahead of the next entry. — Read More

#cyber

How Dangerous Is Anthropic’s Mythos AI?

Last month, Anthropic made a remarkable announcement about its new model, Claude Mythos Preview: it was so good at finding security vulnerabilities in software that the company would not release it to the general public. Instead, it would only be available to a select group of companies to scan and fix their own software.

The announcement requires context—but it contained an essential truth.

While Anthropic’s model is really good at finding software vulnerabilities, so are other models. The UK’s AI Security Institute found that OpenAI’s GPT-5.5, already generally available, is comparable in capability. The company Aisle reproduced Anthropic’s published results with smaller, cheaper models. — Read More

#cyber

Our evaluation of OpenAI’s GPT-5.5 cyber capabilities

In April, our evaluation of an early snapshot of Anthropic’s Claude Mythos Preview found that it represented a step up in cyber performance over previous frontier models and was the first to complete our corporate network attack simulation end-to-end, a multi-step exercise we estimate would take a human around 20 hours. A key question was whether this reflected a breakthrough specific to one model, or part of a broader trend. Results from an early checkpoint of GPT-5.5 suggest the latter: a second model, from a different developer, now reaches a similar level of performance on our cyber. — Read More

#cyber

LLMs can hide text in other text of the same length

A meaningful text can be hidden inside another, completely different yet still coherent and plausible, text of the same length. For example, a tweet containing a harsh political critique could be embedded in a tweet that celebrates the same political leader, or an ordinary product review could conceal a secret manuscript. This uncanny state of affairs is now possible thanks to Large Language Models, and in this paper we present Calgacus, a simple and efficient protocol to achieve it. We show that even modest 8-billion-parameter open-source LLMs are sufficient to obtain high-quality results, and a message as long as this abstract can be encoded and decoded locally on a laptop in seconds. The existence of such a protocol demonstrates a radical decoupling of text from authorial intent, further eroding trust in written communication, already shaken by the rise of LLM chatbots. We illustrate this with a concrete scenario: a company could covertly deploy an unfiltered LLM by encoding its answers within the compliant responses of a safe model. This possibility raises urgent questions for AI safety and challenges our understanding of what it means for a Large Language Model to know something. — Read More

#cyber

GTIG AI Threat Tracker: Adversaries Leverage AI for Vulnerability Exploitation, Augmented Operations, and Initial Access

Since our February 2026 report on AI-related threat activity, Google Threat Intelligence Group (GTIG) has continued to track a maturing transition from nascent AI-enabled operations to the industrial-scale application of generative models within adversarial workflows. This report, based on insights derived from Mandiant incident response engagements, Gemini, and GTIG’s proactive research, highlights the dual nature of the current threat environment where AI serves as both a sophisticated engine for adversary operations and a high-value target for attacks.

… For the first time, GTIG has identified a threat actor using a zero-day exploit that we believe was developed with AI. The criminal threat actor planned to use it in a mass exploitation event but our proactive counter discovery may have prevented its use. Threat actors associated with the People’s Republic of China (PRC) and the Democratic People’s Republic of Korea (DPRK) have also demonstrated significant interest in capitalizing on AI for vulnerability discovery. — Read More

#cyber