A revisit of remote Spectre attacks on Cloudflare Workers

Cloudflare researchers discovered a vulnerability in their Dynamic Process Isolation defense that allowed remote Spectre attacks to leak sensitive data at up to 12 bits per second with 99% accuracy in their Workers production environment. In response, Cloudflare strengthened their defenses by integrating the V8 Sandbox and additional in-process isolation mechanisms to reduce the risk of memory disclosure attacks. The attack has already been mitigated in production, with no evidence of actual exploitation over the past three years.