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CVE PROGRAM SOURCE RECORD7.4 High

CVE-2026-32887

Effect Bug: `AsyncLocalStorage` context lost/contaminated inside Effect fibers under concurrent load with RPC

Description

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Effect-TS effect

  • < 3.20.0affected

References