CVE-2026-42047 HIGH

CVE-2026-42047: Inngest TypeScript SDK exposes environment variables via serve() handler on unhandled HTTP methods

Vendor Inngest
Product inngest-js
Weakness CWE-200 · Info exposure
Published May 7, 2026
Last update May 8, 2026

CVSS base score

8.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

What the vulnerability does

01Description

Inngest is a platform for running event-driven and scheduled background functions with queueing, retries, and step orchestration. Versions 3.22.0 through 3.53.1 contain a vulnerability that allows unauthenticated remote attackers to exfiltrate environment variables from the host process via the serve() HTTP handler. The serve() handler implements GET, POST, and PUT methods. Requests using PATCH, OPTIONS, or DELETE fall through to a generic handler that returns diagnostic information. A change introduced in v3.22.0 caused this diagnostic response to include the contents of process.env, exposing any secrets, API keys, or credentials present in the environment. An application is vulnerable if its serve() endpoint is reachable via PATCH, OPTIONS, or DELETE requests, which is common in setups like Next.js Pages Router or Express's app.use(...). Not affected are Next.js App Router handlers that export only GET, POST, and PUT, and applications using the connect worker method. This issue has been fixed in version 3.54.0. To work around this issue if upgrading is not immediately possible, restrict the serve() endpoint at the framework or reverse-proxy layer to accept only GET, POST, and PUT. The Inngest serve() endpoint does not require any other HTTP methods.

Key dates

02Disclosure timeline

May 7, 2026 CVE published
May 8, 2026 Record updated