GHSA-rcqf-f6h2-ccg9 - Highcharts Dashboards parses sidebar component labels as HTML
### Impact
The component language strings shown in the edit mode sidebar are parsed as HTML rather than inserted as text. An attacker who controls those language options can supply markup carrying event handlers, which execute in the origin of the page hosting the dashboard once the sidebar renders the affected labels. Exploitation requires that untrusted data reach the Dashboards language configuration and that a user open the edit mode sidebar.
### Workarounds
Until you can upgrade, patch `EditMode` once at application startup. The hook runs before the sidebar is built, so the labels are already harmless by the time they are rendered. Assigning a string to `textContent` and reading back `innerHTML` turns any markup into literal text, which is exactly what the fixed version renders.
After importing the module, use this code snipped once, before any board is created.
```js
{
const EditMode = window.Dashboards?.EditMode;
const escapeHTML = (text) => text
.replace(/&/g, '&')
.replace(/</g, '<')
.replace(/>/g, '>');
const patched = new WeakSet();
const originalInit = EditMode.prototype.init;
EditMode.prototype.init = function (...args) {
const labels = this.lang?.sidebar;
if (labels && !patched.has(this)) {
patched.add(this);
for (const key of Object.keys(labels)) {
if (typeof labels[key] === 'string') {
labels[key] = escapeHTML(labels[key]);
}
}
}
return originalInit.apply(this, args);
};
}
```
If your application does not need Edit Mode, leaving it disabled (`editMode.enabled: false`) removes the exposure as well.
### Obtaining the patched version
The patched releases are available from all the usual distribution channels. With npm, upgrade the affected package to the patched version listed above, for example `npm install @highcharts/dashboards@4.2.3`. If you load Highcharts Dashboa
HIGH
Severity & confidence
Source severityhigh
Platform severityhigh
Confidencehigh
Exploitationunknown
CVSS-
Affected
Vendors@highcharts
Products@highcharts/dashboards
Reporting sources (2)
GitHub Security Advisories
NIST NVD - National Vulnerability Database
Timeline & provenance
Published2026-10-28T19:56:57
Last updated2026-10-31T19:07:17
Ingested2026-10-28T19:58:58
FreshnessNEAR-REAL-TIME
Threat typeadvisory
Recommended action
Review the advisory and upgrade affected packages to the first patched version.
Next steps
- Identify affected systems in your environment.
- Apply the vendor patch or mitigation guidance.
- Review logs for indicators described in the advisory.
- Follow the affected vendor/product to track updates.
Confidence explanation
Reported by a government or cert-grade source (CISA, NCSC, NVD, ENISA, MSRC).
Source type: vendor ยท Original: GitHub Security Advisories