What is CVE-2020-29454?

CVE-2020-29454 is a medium-severity vulnerability in Umbraco Cms, classified under Incorrect Authorization. CVSS score: 4.3/10. Published 2020-12-02.

How severe is CVE-2020-29454?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Umbraco Cms

CVE-2020-29454

Editors/LogViewerController.cs in Umbraco through 8.9.1 allows a user to visit a logviewer endpoint even if they lack Applications.Settings access.

Vulnerability class: Broken Access Control

Published 2020-12-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.009 (58.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Umbraco Cms

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

github.com/umbraco/Umbraco-CMS/pull/9361 (Third Party Advisory)

Frequently asked questions

What is CVE-2020-29454?: CVE-2020-29454 is a medium-severity vulnerability in Umbraco Cms, classified under Incorrect Authorization. CVSS score: 4.3/10. Published 2020-12-02.
How severe is CVE-2020-29454?: Medium severity. CVSS v3 base score is 4.3 out of 10.