Vulnerability record/PUBLISHED/Published Oct 27, 2026 19:36:28 UTC

CVE-2026-116688

CKEditor 5 is a modern JavaScript rich-text editor with an MVC architecture. From 45.0.0 until 47.7.4 and 48.5.1, the engine uses a vulnerable es-toolkit version whose prototype-pollution behavior can be reached while CKEditor processes incoming style attribute values. Crafted editor content can thereby cause unauthorized JavaScript execution in the browser. This issue is fixed in versions 47.7.4 and 48.5.1.

Base score8.1/ 10

SeverityHighCVSS 3.1

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes

Base severityHigh

Attack vectorNetworkAV

Attack complexityLowAC

Privileges requiredLowPR

User interactionNoneUI

ScopeUnchangedS

Confidentiality impactHighC

Integrity impactHighI

Availability impactNoneA

CVSS vector stringCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering AuthorityGitHub_M

Last updatedOct 27, 2026 19:36:28 UTC

PublishedOct 27, 2026 19:36:28 UTC

ReservedOct 26, 2026 20:00:59 UTC