Revisiting Spectre Attacks on Cloudflare Workers
๐ In 2024โ2025 research, Cloudflare reassessed remote Spectre attacks against Cloudflare Workers and tested defenses introduced in 2021, notably Dynamic Process Isolation (DyPrIs). The team rebuilt a production proof-of-concept showing a reliable remote Spectre leak under production workloads, found a DyPrIs limitation, and implemented further mitigations including the V8 Sandbox and in-process isolation. The report emphasizes the attack was mitigated in production and no active exploitation was observed in the past three years.
