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 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.
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).
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).
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.
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.
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.