Origin Validation Error Affecting locize package, versions <4.0.21
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-LOCIZE-16421454
- published5 May 2026
- disclosed22 Apr 2026
- creditUnknown
Introduced: 22 Apr 2026
NewCVE-2026-41886 (opens in a new tab)How to fix?
Upgrade locize to version 4.0.21 or higher.
Overview
locize is a This package adds the incontext editor to your i18next setup.
Affected versions of this package are vulnerable to Origin Validation Error in the window.addEventListener message handler due to missing validation of the event.origin property. An attacker can execute arbitrary JavaScript, inject malicious CSS, or hijack internal handler processes by sending crafted postMessage events from a malicious origin. This is only exploitable if the attacker-controlled page shares a window reference with the target, such as through an iframe, window.opener, or parent frame relationship.