CVE-2026-118250: Highcharts: dotted series.keys paths write to Object.prototype
Highcharts JS is a JavaScript charting library based on SVG. From 6.1.0 until 11.4.9, 12.6.1, and 3.1.0, Highcharts follows dot-separated series.keys paths without filtering each segment. An attacker who controls series.keys and matching point data can use a path through proto to assign arbitrary named properties to Object.prototype. Those properties are visible to all JavaScript in the page, and no user interaction is required beyond rendering the chart. This issue is fixed in 11.4.9, 12.6.1, and 3.1.0.
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Highcharts JSto a version that resolves this vulnerability.Fixed in 11.4.9 - Upgrade
Upgrade
Highcharts JSto a version that resolves this vulnerability.Fixed in 12.6.1 - Upgrade
Upgrade
Highcharts JSto a version that resolves this vulnerability.Fixed in 3.1.0
Event History
Frequently Asked Questions
Who is exposed to this issue?
Applications using affected Highcharts versions are exposed when an attacker can control both series.keys and the corresponding point data used to render a chart. The injected properties are then visible to all JavaScript running on that page.
Does exploitation require user interaction?
No. Rendering a chart containing attacker-controlled series.keys and matching point data is sufficient; no additional user interaction is required.
Which versions contain the fix?
The issue is fixed in Highcharts 11.4.9, 12.6.1, and 3.1.0. Affected versions include releases from 6.1.0 up to those fixed releases.