VULNERABILITY INTELLIGENCE

CVE-2023-28439

CVSS score4.7 MEDIUM
EPSS probability0.73%
CISA KEVNot currently listed
Published2023-03-22
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N

Description

CKEditor4 is an open source what-you-see-is-what-you-get HTML editor. A cross-site scripting vulnerability has been discovered affecting Iframe Dialog and Media Embed packages. The vulnerability may trigger a JavaScript code after fulfilling special conditions: using one of the affected packages on a web page with missing proper Content Security Policy configuration; initializing the editor on an element and using an element other than `<textarea>` as a base; and destroying the editor instance. This vulnerability might affect a small percentage of integrators that depend on dynamic editor initialization/destroy mechanism. A fix is available in CKEditor4 version 4.21.0. In some rare cases, a security fix may be considered a breaking change. Starting from version 4.21.0, the Iframe Dialog plugin applies the `sandbox` attribute by default, which restricts JavaScript code execution in the iframe element. To change this behavior, configure the `config.iframe_attributes` option. Also starting from version 4.21.0, the Media Embed plugin regenerates the entire content of the embed widget by default. To change this behavior, configure the `config.embed_keepOriginalContent` option. Those who choose to enable either of the more permissive options or who cannot upgrade to a patched version should properly configure Content Security Policy to avoid any potential security issues that may arise from embedding iframe elements on their web page.

Weakness classification

  • security-advisories@github.com: CWE-79
  • nvd@nist.gov: CWE-79

Primary references