CVE-2021-37695: Execution of JavaScript code using malformed HTML in ckeditor

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-08-13 · updated 2026-06-17
Weakness: CWE-79

Description

ckeditor is an open source WYSIWYG HTML editor with rich content support. A potential vulnerability has been discovered in CKEditor 4 [Fake Objects](https://ckeditor.com/cke4/addon/fakeobjects) 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.

Affected products

ckeditor4: before 4.16.2 — fixed in 4.16.2
Debian Linux: 9.0
Fedoraproject Fedora: 33, 34, 35
Oracle Corporation Application Express: before 21.1.4 — fixed in 21.1.4
Oracle Banking Party Management: 2.7.0
Oracle Corporation Oracle Commerce Guided Search / Oracle Commerce Experience Manager: 11.3.2
Oracle Corporation Commerce Merchandising: 11.3.2
Oracle Documaker: 12.6.3, 12.6.4
Oracle Corporation Financial Services Analytical Applications Infrastructure: from 8.0.7 through 8.1.1; 8.0.3
Oracle Financial Services Model Management And Governance: from 8.0.8.0.0 through 8.1.0.0.0
Oracle Corporation JD Edwards EnterpriseOne Tools: before 9.2.6.0 — fixed in 9.2.6.0
Oracle Corporation PeopleSoft Enterprise PT PeopleTools: 8.57, 8.58, 8.59

How to fix

Upgrade to a fixed version: ckeditor4 4.16.2; Oracle Corporation Application Express 21.1.4; Oracle Corporation JD Edwards EnterpriseOne Tools 9.2.6.0. Check the vendor advisory for mitigations.

References

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