Impact A Cross-Site Scripting (XSS) vulnerability has been discovered in the General HTML Support feature. This vulnerability could be triggered by inserting specially crafted markup, leading to unauthorized JavaScript code execution, if the editor instance used an unsafe General HTML Support configuration.

This vulnerability affects only installations where the editor configuration meets the following criteria:

General HTML Support is enabled, General HTML Support configuration allows inserting unsafe markup (see Security section to learn more).

Patches The problem has been recognized and patched. The fix will be available in version 47.6.0 (and above).

Workarounds CKEditor 5 recommends configuring General HTML Support securely to ensure that unsafe content is not accepted. Please refer to the Security section for detailed guidance.

Credits CKEditor 5 would like to thank: - Emilio Kevin - Jeongwoo Lee, Younsoung Kim, Minseok Kim and Jinyeong Kim from ENKI Whitehat

for responsibly reporting this vulnerability.

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

A reflected cross-site scripting (XSS) vulnerability in CKeditor v46.1.0 & Angular v18.0.0 allows attackers to execute arbitrary code in the context of a user's browser via injecting a crafted payload.

A vulnerability was detected in ZenCart 2.1.0. Affected by this vulnerability is an unknown functionality of the component CKEditor. The manipulation leads to cross site scripting. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. The vendor declares this as "intended behavior, allowed for authorized administrators".

Impact During a recent internal audit, we identified a Cross-Site Scripting (XSS) vulnerability in the CKEditor 5 real-time collaboration package. This vulnerability can lead to unauthorized JavaScript code execution and affects user markers, which represent users' positions within the document.

This vulnerability affects only installations with Real-time collaborative editing enabled.

Patches The problem has been recognized and patched. The fix will be available in version 44.2.1 (and above).

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

Impact During a recent internal audit, we identified a Cross-Site Scripting (XSS) vulnerability in the CKEditor 5 clipboard package. This vulnerability could be triggered by a specific user action, leading to unauthorized JavaScript code execution, if the attacker managed to insert a malicious content into the editor, which might happen with a very specific editor configuration.

This vulnerability affects only installations where the editor configuration meets the following criteria:

1. The Block Toolbar plugin is enabled. 1. One of the following plugins is also enabled: - General HTML Support with a configuration that permits unsafe markup. - HTML Embed.

Patches The problem has been recognized and patched. The fix will be available in version 43.1.1 (and above), and explicitly in version 41.3.2.

Workarounds It's highly recommended to update to the version 43.1.1 or higher. However, if the update is not an option, we recommend disabling the block toolbar plugin.

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

Affected packages The vulnerability has been discovered in Code Snippet GeSHi plugin. All integrators that use GeSHi syntax highlighter on the backend side can be affected.

Impact A potential vulnerability has been discovered in CKEditor 4 Code Snippet GeSHi plugin. The vulnerability allowed a reflected XSS attack by exploiting a flaw in the GeSHi syntax highlighter library hosted by the victim.

The GeSHi library was included as a vendor dependency in CKEditor 4 source files. In a specific scenario, an attacker could craft a malicious script that could be executed by sending a request to the GeSHi library hosted on a PHP web server.

Patches

The GeSHi library is no longer actively maintained. Due to the lack of ongoing support and updates, potential security vulnerabilities have been identified with its continued use. To mitigate these risks and enhance the overall security of the CKEditor 4, we have decided to completely remove the GeSHi library as a dependency. This change aims to maintain a secure environment and reduce the risk of any security incidents related to outdated or unsupported software.

To integrators who still want to use the GeSHi syntax highlighter, we recommend manually adding the GeSHi library . Please be aware of and understand the potential security vulnerabilities associated with its use.

The fix is be available in version 4.25.0-lts.

Acknowledgements

The CKEditor 4 team would like to thank Jiasheng He from Qihoo 360 for recognizing and reporting this vulnerability.

For more information

Email us at security@cksource.com if you have any questions or comments about this advisory.

Affected packages The vulnerability has been discovered in the samples that use the preview feature:

samples/old//.html plugins/[plugin name]/samples//.html

All integrators that use these samples in the production code can be affected.

Impact

A potential vulnerability has been discovered in one of CKEditor's 4 samples that are shipped with production code. The vulnerability allowed to execute JavaScript code by abusing the misconfigured preview feature. It affects all users using the CKEditor 4 at version < 4.24.0-lts with affected samples used in a production environment.

Patches The problem has been recognized and patched. The fix will be available in version 4.24.0-lts.

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

Acknowledgements The CKEditor 4 team would like to thank Marcin Wyczechowski & Michał Majchrowicz AFINE Team for recognizing and reporting this vulnerability.

Affected packages The vulnerability has been discovered in the core HTML parsing module and may affect all editor instances that: Enabled full-page editing mode, or enabled CDATA elements in Advanced Content Filtering configuration (defaults to script and style elements).

Impact

A potential vulnerability has been discovered in CKEditor 4 HTML processing core module. The vulnerability allowed to inject malformed HTML content bypassing Advanced Content Filtering mechanism, which could result in executing JavaScript code. An attacker could abuse faulty CDATA content detection and use it to prepare an intentional attack on the editor. It affects all users using the CKEditor 4 at version < 4.24.0-lts.

Patches The problem has been recognized and patched. The fix will be available in version 4.24.0-lts.

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

Acknowledgements The CKEditor 4 team would like to thank Michal Frýba from ALEF NULA for recognizing and reporting this vulnerability.

A unrestricted file upload vulnerability was discovered in the ‘Browse and upload images’ feature of the CKEditor v1.2.3 plugin for Redmine, which allows arbitrary files to be uploaded to the server.

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.iframeattributes 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.embedkeepOriginalContent 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.

DISPUTED CKSource CKEditor 5 35.4.0 was discovered to contain a cross-site scripting (XSS) vulnerability via the Full Featured CKEditor5 widget. NOTE: the vendor's position is that this is not a vulnerability. The CKEditor 5 documentation discusses that it is the responsibility of an integrator (who is adding CKEditor 5 functionality to a website) to choose the correct security settings for their use case. Also, safe default values are established (e.g., config.htmlEmbed.showPreviews is false).

CKEditor 5 is a JavaScript rich text editor. A cross-site scripting vulnerability has been discovered affecting three optional CKEditor 5's packages in versions prior to 35.0.1. The vulnerability allowed to trigger a JavaScript code after fulfilling special conditions. The affected packages are @ckeditor/ckeditor5-markdown-gfm, @ckeditor/ckeditor5-html-support, and @ckeditor/ckeditor5-html-embed. The specific conditions are 1) Using one of the affected packages. In case of ckeditor5-html-support and ckeditor5-html-embed, additionally, it was required to use a configuration that allows unsafe markup inside the editor. 2) Destroying the editor instance and 3) Initializing the editor on an element and using an element other than <textarea> as a base. The root cause of the issue was a mechanism responsible for updating the source element with the markup coming from the CKEditor 5 data pipeline after destroying the editor. This vulnerability might affect a small percent of integrators that depend on dynamic editor initialization/destroy and use Markdown, General HTML Support or HTML embed features. The problem has been recognized and patched. The fix is available in version 35.0.1. There are no known workarounds for this issue.

CKEditor is vulnerable to cross-site scripting, caused by improper validation of user-supplied input. A remote authenticated attacker could exploit this vulnerability to inject malicious script into a Web page which would be executed in a victim's Web browser within the security context of the hosting Web site, once the page is viewed. An attacker could use this vulnerability to steal the victim's cookie-based authentication credentials.

CKEditor is vulnerable to a denial of service, caused by a regular expression denial of service (ReDoS) flaw in the dialog plugin. By sending a specially-crafted regex input, a remote attacker could exploit this vulnerability to cause a significant performance drop and results in a browser tab freeze.

Affected packages The vulnerability has been discovered in the core HTML processing module and may affect all plugins used by CKEditor 4.

Impact A potential vulnerability has been discovered in CKEditor 4 HTML processing core module. The vulnerability allowed to inject malformed comments HTML bypassing content sanitization, which could result in executing JavaScript code. It affects all users using the CKEditor 4 at version < 4.17.0.

Patches The problem has been recognized and patched. The fix will be available in version 4.17.0.

For more information Email us at security@cksource.com if you have any questions or comments about this advisory.

Acknowledgements The CKEditor 4 team would like to thank William Bowling (wbowling) for recognizing and reporting this vulnerability.

CKEditor4 is an open source WYSIWYG HTML editor. In affected versions a vulnerability has been discovered in the Advanced Content Filter (ACF) module and may affect all plugins used by CKEditor 4. The vulnerability allowed to inject malformed HTML bypassing content sanitization, which could result in executing JavaScript code. It affects all users using the CKEditor 4 at version < 4.17.0. The problem has been recognized and patched. The fix will be available in version 4.17.0.

ckeditor is an open source WYSIWYG HTML editor with rich content support. A potential vulnerability has been discovered in CKEditor 4 Fake Objects package. The vulnerability allowed to inject malformed Fake Objects HTML, which could result in executing JavaScript code. It affects all users using the CKEditor 4 plugins listed above at version < 4.16.2. The problem has been recognized and patched. The fix will be available in version 4.16.2.

ckeditor is an open source WYSIWYG HTML editor with rich content support. A potential vulnerability has been discovered in CKEditor 4 Clipboard package. The vulnerability allowed to abuse paste functionality using malformed HTML, which could result in injecting arbitrary HTML into the editor. It affects all users using the CKEditor 4 plugins listed above at version >= 4.5.2. The problem has been recognized and patched. The fix will be available in version 4.16.2.

ckeditor is an open source WYSIWYG HTML editor with rich content support. A vulnerability has been discovered in the clipboard Widget plugin if used alongside the undo feature. The vulnerability allows a user to abuse undo functionality using malformed widget HTML, which could result in executing JavaScript code. It affects all users using the CKEditor 4 plugins listed above at version >= 4.13.0. The problem has been recognized and patched. The fix will be available in version 4.16.2.

A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript code through a crafted comment because --!> is mishandled.

CKEditor 5 provides a WYSIWYG editing solution. This CVE affects the following npm packages: ckeditor5-engine, ckeditor5-font, ckeditor5-image, ckeditor5-list, ckeditor5-markdown-gfm, ckeditor5-media-embed, ckeditor5-paste-from-office, and ckeditor5-widget. Following an internal audit, a regular expression denial of service (ReDoS) vulnerability has been discovered in multiple CKEditor 5 packages. The vulnerability allowed to abuse particular regular expressions, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 5 packages listed above at version <= 26.0.0. The problem has been recognized and patched. The fix will be available in version 27.0.0.

CKEditor 5 is an open source rich text editor framework with a modular architecture. The CKEditor 5 Markdown plugin (@ckeditor/ckeditor5-markdown-gfm) before version 25.0.0 has a regex denial of service (ReDoS) vulnerability. The vulnerability allowed to abuse link recognition regular expression, which could cause a significant performance drop resulting in browser tab freeze. It affects all users using CKEditor 5 Markdown plugin at version <= 24.0.0. The problem has been recognized and patched. The fix will be available in version 25.0.0.

It was possible to execute a ReDoS-type attack inside CKEditor 4 before 4.16 by persuading a victim to paste crafted URL-like text into the editor, and then press Enter or Space (in the Autolink plugin).

CKEditor is vulnerable to a denial of service, caused by a regular expression denial of service (ReDoS) flaw in the Advanced Tab for Dialogs plugin. By persuading a victim to paste specially-crafted text into the Styles input of specific dialogs, a remote attacker could exploit this vulnerability to cause a denial of service condition.

A cross-site scripting (XSS) vulnerability in the Color Dialog plugin for CKEditor 4.15.0 allows remote attackers to run arbitrary web script after persuading a user to copy and paste crafted HTML code into one of editor inputs.

A cross-site scripting (XSS) vulnerability in the WSC plugin through 5.5.7.5 for CKEditor 4 allows remote attackers to run arbitrary web script inside an IFRAME element by injecting a crafted HTML element into the editor.

A cross-site scripting (XSS) vulnerability in the HTML Data Processor for CKEditor 4.0 before 4.14 allows remote attackers to inject arbitrary web script through a crafted "protected" comment (with the ckeprotected syntax).

hookfiledownload in the CKEditor module 7.x-1.4 for Drupal does not properly restrict access to private files, which allows remote attackers to read private files via a direct request.

CKEditor 4.x before 4.11.0 allows user-assisted XSS involving a source-mode paste.

Cross-site scripting (XSS) vulnerability in the Link package for CKEditor 5 before 10.0.1 allows remote attackers to inject arbitrary web script through a crafted href attribute of a link (A) element.