# CVE-2026-118250: Highcharts: dotted series.keys paths write to Object.prototype


- **Severity:** High 7.2 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** GHSA-rmqc-xvr3-v46c

## What is CVE-2026-118250?

CVE-2026-118250 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 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.

Weakness: CWE-1321 (Improperly Controlled Modification of Object Prototype Attributes)

## Which versions are affected by CVE-2026-118250?

6 open source packages ship an affected version, including highcharts.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `highcharts` | npm | From 12.0.0 | 12.6.1 |
| `highcharts` | npm | From 12.0.0 | 12.6.1 |
| `highcharts` | npm | From 13.0.0 | 13.1.0 |
| `highcharts` | npm | From 13.0.0 | 13.1.0 |
| `highcharts` | npm | From 6.1.0 | 11.4.9 |
| `highcharts` | npm | From 6.1.0 | 11.4.9 |

## How do I fix CVE-2026-118250?

Upgrade highcharts to a fixed version for your release line: 12.6.1, 13.1.0 or 11.4.9.

## Is CVE-2026-118250 being exploited?

There is no known exploitation of CVE-2026-118250 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-118250 and fix it if it is affected.

What it is: CVE-2026-118250 is a high-severity vulnerability in highcharts, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-118250 in the wild and no public exploit code.

Affected packages and fixed versions:
- highcharts (npm): affected from 12.0.0; fixed in 12.6.1
- highcharts (npm): affected from 12.0.0; fixed in 12.6.1
- highcharts (npm): affected from 13.0.0; fixed in 13.1.0
- highcharts (npm): affected from 13.0.0; fixed in 13.1.0
- highcharts (npm): affected from 6.1.0; fixed in 11.4.9
- highcharts (npm): affected from 6.1.0; fixed in 11.4.9

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-118250/ (Markdown: https://insights.sbomify.com/CVE-2026-118250/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-118250
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-118250
- OSV: https://osv.dev/vulnerability/CVE-2026-118250

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-118250/
Summaries are generated and may contain mistakes; the official description above is the record.