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Umbraco CMS vulnerable to stored XSS

Moderate severity GitHub Reviewed Published May 24, 2022 to the GitHub Advisory Database • Updated Aug 23, 2023

Package

nuget UmbracoCms.Core (NuGet)

Affected versions

<= 8.9.1

Patched versions

None

Description

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.

References

Published by the National Vulnerability Database Dec 30, 2020
Published to the GitHub Advisory Database May 24, 2022
Reviewed Jul 13, 2023
Last updated Aug 23, 2023

Severity

Moderate
5.4
/ 10

CVSS base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weaknesses

CVE ID

CVE-2020-5809

GHSA ID

GHSA-95qr-67rx-9pgh

Source code

Checking history
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