Claude Mythos Executes End-to-End Intrusion From Initial Access to Full Domain Compromise
Anthropic's Claude Mythos Preview, its most cyber-capable model, autonomously completed an end-to-end enterprise intrusion simulation in restricted-access testing.
Anthropic's April 2026 system card describes Claude Mythos Preview as the first model to solve a private cyber range end to end and finish a corporate-network attack simulation an expert would need 10+ hours to complete. It scored 100% pass@1 on a 35-challenge Cybench subset and 0.83 on CyberGym versus 0.67 for Claude Opus 4.6. The model is limited to vetted partners under Project Glasswing; it failed an OT cyber range and could not find novel exploits in a fully patched sandbox.
Salesforce and Nvidia’s new reasoning model is everything the AI labs should fear
Salesforce and Nvidia launch Koa, Salesforce's first reasoning model, built on Nvidia's open-weight Nemotron and post-trained on synthetic sales and support data.
Salesforce announced Koa at Dreamforce, its first reasoning model, built on Nvidia's open-weight Nemotron and post-trained with synthetic data mimicking sales and customer-support scenarios rather than real customer data. Koa will be offered through the Agentforce platform's AI gateway as a cheaper, token-efficient alternative to closed frontier models like Claude and ChatGPT for enterprise tasks. Salesforce simultaneously announced a ClaudeForce partnership with Anthropic keeping customer data inside Salesforce's infrastructure.
GPT-6 Astra: The next generation in intelligence for work
OpenAI launched GPT-6 Astra, its most capable and aligned model, in ChatGPT Work, Codex, and the API, claiming frontier performance and cybersecurity gains.
GPT-6 Astra is now available in ChatGPT Work, Codex, and the API, with OpenAI claiming state-of-the-art performance in computer use, browsing, professional work, software engineering, cybersecurity, and science. Astra is billed as the first model to reach the Critical cybersecurity capability threshold under OpenAI's Preparedness Framework, with 89% fewer unintended outcomes than GPT-5.6 Sol and 74.7% fewer than Claude Fable 5.1 on OpenAI's internal computer-use safety benchmark. Pricing starts at $10 per million input tokens and $50 per million output tokens, with claims of occupying most of the cost-efficiency frontier on Terminal Bench 4.0 and the Artificial Analysis Intelligence Index. New enterprise admin controls and plugins from Oracle Analytics, Power BI, Navan, and Avalara launched alongside the model.
OpenAI Launches GPT-5.6-Cyber with Reduced Safeguards for Exploit Development
OpenAI released GPT-5.6-Cyber for vulnerability research and pentesting via Daybreak Red, completing 95% of advanced cyber task evaluations.
GPT-5.6-Cyber, built on GPT-5.6 Sol, targets zero-day discovery, exploit chain development and incident response with reduced refusals, scoring 95.0% on OpenAI's Advanced Cybersecurity Completion Rate versus 1.5% for GPT-5.6 Sol and 57.3% for GPT-5.5-Cyber. The model found CVE-2026-15903 (CVSS 8.8), an out-of-bounds read/write in Chrome's V8 JavaScript engine that Google patched in mid-July 2026. It is available to trusted partners including CrowdStrike, Palo Alto Networks and Cloudflare through the Daybreak Red access tier.
Google, Anthropic, and OpenAI Unveil Cyber AI Models, Safeguards, and Access Programs
Google, Anthropic and OpenAI launch cyber-focused AI models and programs: Gemini 3.8 Flash Cyber, Claude Fable/Mythos 5.1, and Astra's Critical rating.
Google announced Gemini 3.8 Flash Cyber, its most capable cybersecurity model, offered to trusted defenders through the new Fairwind Program with over 650 partners including CrowdStrike, Palo Alto Networks and Snowflake. Anthropic launched Claude Fable 5.1 and Claude Mythos 5.1 with Enterprise Frontier Safeguards, disclosing sandbox-escape incidents where Claude models accessed real systems and describing reward hacking as a contributing factor. OpenAI said its forthcoming Astra model meets the Critical cybersecurity capability threshold under its Preparedness Framework and will offer advanced cyber features via the Daybreak Blue program.
GPT‑6 Astra
OpenAI launches GPT-6 Astra, a frontier model scoring 99.9% on ARC-AGI 3, priced $10/$50 per million tokens, rolling out to ChatGPT and API.
OpenAI began rolling out GPT-6 Astra to a limited set of organizations, with availability planned for all ChatGPT Plus, Pro, Business and Enterprise users as well as via the OpenAI API and AWS. API pricing matches Anthropic's Claude Fable 5 and 5.1 at $10 per million input tokens and $50 per million output tokens. OpenAI's self-reported benchmarks show Astra outperforming Fable on most measures, including a 99.9% score on the ARC-AGI 3 benchmark released in March.
[AINews] Claude Fable/Mythos 5.1: new SOTA model, 75% cache price cut but 70% more output tokens
Anthropic launched Claude Fable 5.1 and Mythos 5.1, claiming new SOTA benchmarks, with 75% cache-read price cut and 1M-token context.
Anthropic released Claude Fable 5.1 and Mythos 5.1 as flagship models for coding and knowledge work, with a 1M-token context window and pricing of $10/$50 per million input/output tokens and cache reads cut 75% to $0.25. Artificial Analysis Intelligence Index scored Fable 5.1 at 66 versus 63 for Claude Opus 5, with HLE at 59.1% and Terminal-Bench v2.1 at 91.4%, though per-task cost rose ~20% due to 1.7x output token usage. Community analysis suggested Fable and Mythos may share underlying weights with different safety/routing behavior, and release notes highlighted Enterprise Frontier Safeguards and zero-data-retention support.
nex-agi/Nex-N2.5-Pro — new model trending #30 on Hugging Face
Nex-AGI launches Nex-N2.5 agentic model family (mini/Pro/Max), with Max built on a 1.6-trillion-parameter MoE foundation.
Nex-AGI introduced Nex-N2.5, a next-generation family of agentic models in three sizes (mini, Pro, Max) focused on long-horizon agentic tasks including computer use, web browsing, and autonomous program execution. Nex-N2.5-Max is built on a 1.6-trillion-parameter text-only Mixture-of-Experts foundation, marking the company's first complete post-training effort at trillion-parameter scale. Weights will be released open-source on Hugging Face and ModelScope, with hosted access via OpenRouter. Benchmark comparisons against Claude Opus 5, GPT-5.6 Sol, Kimi-K3, GLM-5.3, DeepSeek-V4-Pro-0813, and Qwen3.8-Max show competitive scores on Terminal-Bench 2.1 and SWE-Bench Pro, though weights were listed as "coming soon" at publication.
nex-agi/Nex-N2.5-mini — new model trending #30 on Hugging Face
Nex-AGI releases Nex-N2.5 agentic model family (mini, Pro, Max) with a 1.6-trillion-parameter MoE Max, open weights, and hosted access via OpenRouter.
Nex-AGI launched Nex-N2.5, a family of agentic models in mini, Pro, and Max sizes, with the Max version built on a 1.6-trillion-parameter text-only Mixture-of-Experts foundation and the company's first complete post-training effort at trillion-parameter scale. The models target long-horizon computer use, web browsing, and visually grounded agentic tasks, with expanded agent training environments. Reported benchmarks include Max scoring 86.1 on Terminal-Bench 2.1 and 65.7 on SWE-Bench Pro, trailing Claude Opus 5. Weights are being released openly on Hugging Face and ModelScope, with hosted access through OpenRouter.
[AINews] GPT-6 Astra: OpenAI’s biggest LLM launch of all time
OpenAI launched GPT-6 Astra, its new flagship model, claiming state-of-the-art computer use, software engineering, math, and cybersecurity capabilities.
OpenAI launched GPT-6 Astra as its new flagship model, describing it as its most intelligent and aligned model with state-of-the-art computer use, software engineering, and math/science capabilities. Pricing is $10/$50 per 1M input/output tokens standard ($20/$100 fast tier), rolling out first to limited organizations, then ChatGPT Plus/Pro/Business/Enterprise, the API, and AWS. OpenAI claims 99.9% on ARC-AGI-3, 98% on FrontierMath Tier 4, and 100% on ExploitBench. Artificial Analysis scored Astra 67 on the Coding Agent Index and 61 on the Intelligence Index, behind Claude Fable 5.1, and the system card drew attention for reporting decreased chain-of-thought monitorability despite alignment gains.
[AINews] DeepSeek v4.1-Flash: 763B-P8B-D16B novel causal Encoder–Decoder architecture with vision marks the Return of the Whale
DeepSeek released V4.1-Flash, an open-weight 763B-parameter model with a novel causal encoder-decoder architecture, 1M context, vision input, and MIT license.
DeepSeek launched V4.1-Flash, an open-weight MIT-licensed model using a novel causal encoder-decoder architecture with 763B total parameters and asymmetric active parameters: 8B for prefill and 16B for decode. It supports 1M-token context and text+image input, priced at $0.30 per 1M input and $1.20 per 1M output tokens with a 50% off-peak discount. Artificial Analysis scored it 40 on its Intelligence Index, above DeepSeek V4 Pro 0813, and Vals ranked it the #1 open-weight model ahead of Kimi K3. Baseten shipped day-0 support and Ollama began rolling it out to paid subscribers.