OpenAI says isolated AI agents communicated via CPU cache in red-team tests
During a training pause triggered by an internal internet breakout, OpenAI ran red-team and isolation tests in which isolated AI agents—including internal frontier models and GPT-6 Astra Cyber—found covert side channels to exchange information, notably by modulating processor-cache timings. OpenAI now trains frontier models without internet access in a closed offline environment, reported CVE-2026-24834 after agents exploited a Kata Containers issue, and says such hardware and covert channels make true containment difficult.