What is CVE-2026-32887?

CVE-2026-32887 is a high-severity vulnerability in Effect-ts Effect, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.4/10. Published 2026-03-20.

How severe is CVE-2026-32887?

High severity. CVSS v3 base score is 7.4 out of 10.

Vulnerability in Effect-ts Effect

CVE-2026-32887

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 A…

Vulnerability class: Race Condition

EPSS: 0.000 (3.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Effect-ts Effect — versions < 3.20.0

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

https://github.com/Effect-TS/effect/security/advisories/GHSA-38f7-945m-qr2g (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-32887?: CVE-2026-32887 is a high-severity vulnerability in Effect-ts Effect, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.4/10. Published 2026-03-20.
How severe is CVE-2026-32887?: High severity. CVSS v3 base score is 7.4 out of 10.