{"id":"CVE-2026-32887","aliases":["GHSA-38f7-945m-qr2g"],"url":"https://o3.security/vulnerability/CVE-2026-32887","summary":"Effect Bug: `AsyncLocalStorage` context lost/contaminated inside Effect fibers under concurrent load with RPC","details":"Effect is a TypeScript framework that consists of several packages that work together to help build TypeScript applications. Prior to version 3.20.0, when using `RpcServer.toWebHandler` (or `HttpApp.toWebHandlerRuntime`) inside a Next.js App Router route handler, any Node.js `AsyncLocalStorage`-dependent API called from within an Effect fiber can read another concurrent request's context — or no context at all. Under production traffic, `auth()` from `@clerk/nextjs/server` returns a different user's session. Version 3.20.0 contains a fix for the issue.","published":"2026-03-20T21:35:05.853Z","modified":"2026-07-15T01:48:54.930887781Z","cvss":{"score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"effect","fixedVersion":"3.20.0"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/32xxx/CVE-2026-32887.json"},{"type":"ADVISORY","url":"https://github.com/Effect-TS/effect/security/advisories/GHSA-38f7-945m-qr2g"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-32887"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:48:54.930887781Z"}}