CVE-2026-32887

Summary

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 Software

VendorProductVersion RangeStatus
Effect-TSeffect< 3.20.0affected

Weaknesses

  • CWE-362: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: partial

References