What is CVE-2026-33638?

CVE-2026-33638 is a medium-severity vulnerability in Lin-snow Ech0, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-03-26.

How severe is CVE-2026-33638?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Lin-snow Ech0

CVE-2026-33638

Ech0 is an open-source, self-hosted publishing platform for personal idea sharing. Prior to version 4.2.0, `GET /api/allusers` is mounted as a public endpoint and returns user records without authentication. This allows remote unauthentica…

Vulnerability class: Broken Access Control

EPSS: 0.000 (8.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Lin-snow Ech0 — versions < 4.2.0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

https://github.com/lin-snow/Ech0/security/advisories/GHSA-m983-7426-5hrj (x_refsource_CONFIRM)
https://github.com/lin-snow/Ech0/commit/acbf1fd71011e6b9e1e6a911128056a19862f681 (x_refsource_MISC)
https://github.com/lin-snow/Ech0/releases/tag/v4.2.0 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-33638?: CVE-2026-33638 is a medium-severity vulnerability in Lin-snow Ech0, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-03-26.
How severe is CVE-2026-33638?: Medium severity. CVSS v3 base score is 5.3 out of 10.