Spectre rears its ugly head again as researchers show some RISC-V chips are susceptible

Researchers have shown that several commercial out-of-order RISC-V processors are susceptible to multiple Spectre variants (Spectre-PHT, BTB, RSB, and STL), demonstrated proof-of-concept exploits that can leak kernel memory (e.g., 338 B/s on a Xuantie C910), and argue that the RISC-V ecosystem lacks the hardware transparency and architectural primitives needed for robust Spectre mitigations; some patches have been submitted upstream and vendors have begun addressing the findings.