Summary
Highcharts Dashboards parses fullscreen labels as HTML
Workarounds
Until you can upgrade, replace Fullscreen.prototype.setButtonText atapplication startup. The replacement is the original method with textContent in place of innerHTML.
If you install Dashboards from npm
Import the module once, before any board is created.
import Fullscreen from '@highcharts/dashboards/es-modules/Dashboards/EditMode/Fullscreen.js';
Fullscreen.prototype.setButtonText = function () {
const editMode = this.board.editMode,
button = editMode?.tools.contextMenu?.items.viewFullscreen;
if (button?.innerElement) {
const lang = editMode.lang;
button.innerElement.textContent =
(this.isOpen ? lang.exitFullscreen : lang.viewFullscreen) || '';
}
};
If you load Dashboards from a <script> tag
The same replacement, taking Fullscreen from the global namespace. It must run after modules/layout and before any board is created.
<script src="https://code.highcharts.com/dashboards/dashboards.js"></script>
<script src="https://code.highcharts.com/dashboards/modules/layout.js"></script>
<script>
{
const Fullscreen = window.Dashboards?.Fullscreen;
Fullscreen.prototype.setButtonText = function () {
const editMode = this.board.editMode,
button = editMode?.tools.contextMenu?.items.viewFullscreen;
if (button?.innerElement) {
const lang = editMode.lang;
button.innerElement.textContent =
(this.isOpen ? lang.exitFullscreen : lang.viewFullscreen) || '';
}
};
}
</script>
If your application does not need Edit Mode, leaving it disabled (editMode.enabled: false) removes the exposure as well. The same applies to the context menu, the label is only reachable when viewFullscreen is among editMode.contextMenu.items.
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/[email protected]. If you load Highcharts Dashboards from a CDN, use a versioned URL, for example https://code.highcharts.com/dashboards/4.2.3/dashboards.js. For more on each installation method, see the installation guide.
Impact
The edit mode fullscreen labels are parsed as HTML when the corresponding control is rendered. An attacker who controls the Dashboards language options can supply markup carrying event handlers, which then execute in the origin of the page hosting the dashboard. Exploitation requires that untrusted data reach the Dashboards language configuration and that the affected control be rendered. Script running this way has the same access to page data, storage and session state as the hosting application.
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-118253? CVE-2026-118253 is a high-severity cross-site scripting (XSS) vulnerability in @highcharts/dashboards (npm), affecting versions >= 1.0.0, < 4.2.3. It is fixed in 4.2.3. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- Which versions of @highcharts/dashboards are affected by CVE-2026-118253? @highcharts/dashboards (npm) versions >= 1.0.0, < 4.2.3 is affected.
- Is there a fix for CVE-2026-118253? Yes. CVE-2026-118253 is fixed in 4.2.3. Upgrade to this version or later.
- Is CVE-2026-118253 exploitable, and should I be worried? Whether CVE-2026-118253 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-118253 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-118253? Upgrade
@highcharts/dashboardsto 4.2.3 or later.