In a new experiment, agents in separate microVMs with no network connection or shared files exchanged information through the CPU cache. The sender evicted data or left it in place. The receiver decoded the message from fast or slow reads, like Morse code.

OpenAI also described using CPU load and the TLS certificate cache as similar channels. The test was not an escape, since the agents had been instructed to communicate.

The channels are extremely slow, but the result matters: network and file isolation alone do not guarantee complete information isolation.