https://blog.ast.moe/en/tags/spectre/Recent posts: GorimuchuHugohttps://blog.ast.moe/en/blog/2026-10-16/Fri, 16 Oct 2026 21:37:01 +0900https://blog.ast.moe/en/blog/2026-10-16/<p>I already knew that SharedArrayBuffer was unavailable by default in browsers as a mitigation for Spectre. But my understanding of Spectre stopped at a vague idea of a memory-related vulnerability.</p> <p>SharedArrayBuffer was a low-level API for shared memory, so I assumed it enabled some kind of memory exploit. I left it at that, without being able to explain how Spectre worked or how an attack used this API.</p> <p>Finally reading about it revealed a different problem. SharedArrayBuffer did not directly let you read somebody else&rsquo;s memory. <strong>Shared memory could build a precise clock.</strong></p>