CVE-2026-118249 Highcharts: series column construction writes to Object.prototype
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-118249?
CVE-2026-118249 is a high-severity vulnerability in highcharts, published on 28 Oct 2026.
Official description
Highcharts JS is a JavaScript charting library based on SVG. From 13.0.0 until 13.1.0, Highcharts builds series data columns by using point option keys directly as column IDs. Own enumerable __proto__ and constructor keys from parsed point objects can therefore direct integer-indexed writes to Object.prototype or the Object constructor. The inherited values affect reads and for-in enumeration across the page and can disrupt rendering or alter consuming application behavior without user interaction beyond rendering the chart. This issue is fixed in 13.1.0.
Weakness: CWE-1321
Which versions are affected by CVE-2026-118249?
2 open source packages ship an affected version, including highcharts.
| Package | Affected | Fixed in |
|---|---|---|
highcharts npm | From 13.0.0 | 13.1.0 |
highcharts npm | From 13.0.0 | 13.1.0 |
How do I fix CVE-2026-118249?
Upgrade highcharts to 13.1.0 or later.
Is CVE-2026-118249 being exploited?
There is no known exploitation of CVE-2026-118249 in the wild and no public exploit code.
Sources
Also known as GHSA-gfvx-2c2g-38wq.