Auth bypass in Codegenieapp Serverless-Express

CVE-2026-4171

A security vulnerability has been detected in CodeGenieApp serverless-express up to 4.17.1. Affected by this issue is some unknown functionality of the file examples/lambda-function-url/packages/api/models/TodoList.ts of the component API Endpoint. The manipulation of the argument userId leads to authorization bypass. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

EPSS: 0.003 (19.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4171?
CVE-2026-4171 is a medium-severity vulnerability in Codegenieapp Serverless-Express, classified under Improper Authorization. CVSS score: 6.3/10. Published 2026-03-16.
How severe is CVE-2026-4171?
Medium severity. CVSS v3 base score is 6.3 out of 10.