Containers are no longer a security boundary. Over the past few months, we’ve seen a crazy amount of Linux kernel vulnerabilities and exploits. This has forced us to rethink the security of infrastructure that relies heavily on the underlying kernel, especially containers. As models become more capable, the barrier to escaping a container has fallen so much that adversaries can now generate working kernel exploits in a single shot. CVE-2026-80521 is one such example. We discovered it using dfs-large1 from @depthfirstlabs and generated the exploit in one shot with GPT-5.6 Sol. The exploit still works on the latest Ubuntu 26.04 release because the fix has not yet been backported. Read our full writeup: depthfirst.com/research/cont…

We received early access to @claudeai Opus 5.5 and evaluated its defensive security capabilities on @depthfirstlabs dfbench. At high reasoning effort, the model achieved 54.9% recall and 48.5% precision, up from 48.1% and 44.2% at medium. Detection cost averaged $8.42 per task, roughly one-third the cost of GPT 5.6 Sol at high and half the cost of Grok 4.7 at high, though with lower recall than both. Surprisingly, increasing reasoning effort improved both recall and precision. We’ve typically seen a tradeoff in our evaluations, with models finding more vulnerabilities at the expense of more false positives. Opus 5.5 improved on both. It also reached 79.5% macro recall on differential analysis, up from 75.3% at medium. At $1.78 per task, it showed strong performance in tracking vulnerabilities across code changes.

Today we're launching the Specialized Intelligence Index (SII): one destination for real-work benchmarks across industries, built by the teams that use them every day. Hear from Fireworks co-founder @the_bunny_chen on the importance of specialized benchmarks: