Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') Affecting umbraco.cms package, versions [7.0.0,7.15.11)[8.0.0,8.18.9)[9.0.0,10.7.0)[11.0.0,11.5.0)[12.0.0,12.2.0)


Severity

Recommended
0.0
low
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.05% (20th percentile)

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  • Snyk IDSNYK-DOTNET-UMBRACOCMS-6124620
  • published13 Dec 2023
  • disclosed12 Dec 2023
  • creditS3ntago

Introduced: 12 Dec 2023

CVE-2023-49279  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Umbraco.Cms to version 7.15.11, 8.18.9, 10.7.0, 11.5.0, 12.2.0 or higher.

Overview

Affected versions of this package are vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'). An attacker with access to the backoffice can upload malicious SVG files containing scripts, which may be executed if another user is tricked into loading the media directly in a browser.

Workaround

Users unable to upgrade to the fixed version can do one of the following:

  1. Implement the server-side file validation https://docs.umbraco.com/umbraco-cms/reference/security/serverside-file-validation

  2. Serve all media from a different host (e.g, cdn) than where Umbraco is hosted.

References

CVSS Scores

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