What is CVE-2020-5809?

CVE-2020-5809 is a medium-severity vulnerability in Umbraco Cms, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2020-12-30.

How severe is CVE-2020-5809?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Umbraco Cms

CVE-2020-5809

A stored XSS vulnerability exists in Umbraco CMS <= 8.9.1 or current. An authenticated user can inject arbitrary JavaScript code into iframes when editing content using the TinyMCE rich-text editor, as TinyMCE is configured to allow iframes by default in Umbraco CMS.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.007 (48.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Umbraco Umbraco_cms
N/a Umbraco Cms — versions <= 8.9.1 or current (unfixed)

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

vulnreport@tenable.com (Exploit, Third Party Advisory, x_refsource_MISC)

Frequently asked questions

What is CVE-2020-5809?: CVE-2020-5809 is a medium-severity vulnerability in Umbraco Cms, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2020-12-30.
How severe is CVE-2020-5809?: Medium severity. CVSS v3 base score is 5.4 out of 10.