CVE-2020-5809: XSS

Published Dec 30, 2020
·
Updated

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.

Affected Software

2 affected components
nuget/UmbracoCms.Core<=8.9.1
Umbraco Umbraco CMS<=8.9.1

Event History

Dec 30, 2020
CVE Published
via MITRE·03:18 PM
Data Sourced
via MITRE·03:18 PM
DescriptionWeakness
May 24, 2022
Advisory Published
05:37 PM

Frequently Asked Questions

1

What is CVE-2020-5809?

CVE-2020-5809 is a stored XSS vulnerability that exists in Umbraco CMS versions <= 8.9.1 or current.

2

How does the vulnerability in Umbraco CMS CVE-2020-5809 work?

An authenticated user can inject arbitrary JavaScript code into iframes when editing content using the TinyMCE rich-text editor in Umbraco CMS, as TinyMCE is configured to allow iframes by default.

3

Is Umbraco CMS version 8.9.1 affected by CVE-2020-5809?

Yes, Umbraco CMS version 8.9.1 is affected by CVE-2020-5809.

4

How severe is the vulnerability in Umbraco CMS CVE-2020-5809?

The severity of the vulnerability in Umbraco CMS CVE-2020-5809 is medium, with a severity score of 5.4.

5

How can I fix the vulnerability in Umbraco CMS CVE-2020-5809?

To fix the vulnerability in Umbraco CMS CVE-2020-5809, it is recommended to update to a version higher than 8.9.1 or apply the necessary security patches.

Contact

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