CVE-2026-118249: Prototype Pollution

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.

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Weakness Type (CWE)

CWE-1321 CWE-1321

References

Other References

https://github.com/highcharts/highcharts/commit/d3357705c8f348904441327e32f50ab528c3a205 https://github.com/highcharts/highcharts/pull/25321 https://github.com/highcharts/highcharts/releases/tag/v13.1.0 https://github.com/highcharts/highcharts/security/advisories/GHSA-gfvx-2c2g-38wq

Frequently Asked Questions

What is CVE-2026-118249? +

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.

How do I check if I'm vulnerable to CVE-2026-118249? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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