CVE-2026-42047
HighWhat is CVE-2026-42047?
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.
CVSS Vector Breakdown
CVSS 3.1Exploitable remotely over the network without requiring access to the local system.
No special conditions required. Exploit can be performed reliably and repeatedly.
No authentication required. Any anonymous user can exploit this vulnerability.
No user interaction required. Exploit runs without any victim action.
Exploiting the vulnerability can affect other components beyond the vulnerable one.
Complete loss of confidentiality. All data on the component may be exposed.
No integrity impact. Data cannot be modified.
No availability impact. Service remains fully operational.
FAQ
CVE-2026-42047 has a CVSS score of 8.6/10, rated as High. This is a high severity vulnerability and should be patched as soon as possible.
CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-42047 scores 8.6/10 (High). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.
The list of devices confirmed to be affected by CVE-2026-42047 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.
Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.