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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.

The Hacker News · 13d agoModel release1

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.

The Hacker News · Aug 11, 2026Model releaseCVE-2026-15903

GPT-6 Astra Scores 100% on ExploitBench as OpenAI Blocks PoC Exploit Requests

OpenAI releases GPT-6 Astra, scoring 100% on ExploitBench, but restricts it to secure code review by blocking PoC exploit generation.

OpenAI officially unveiled GPT-6 Astra days after the model reached the "Critical" cybersecurity capability threshold under its Preparedness Framework. The model claims 100% on ExploitBench (versus 78.5% for GPT-5.6 Sol), 98% on FrontierMath Tier 4, and 99.9% on ARC-AGI-3, and demonstrated exploit development including on two zero-days disclosed between June and August 2026. The released version is limited to secure code review and patching and refuses proof-of-concept exploit requests, with less restrictive safeguards planned via OpenAI Daybreak. OpenAI also launched a $1 billion "Daybreak for Frontline Defenders" program for critical infrastructure sectors and a pilot with the US MS-ISAC for public sector and water system defenders.

The Hacker News · 11d agoModel release1

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.

GBHackers · 7d agoModel release1