CVE-2026-41886
locize is a localization platform that connects code and i18n setup. Prior to version 4.0.21, the locize client SDK registers a window.addEventListener("message", …) handler that dispatches to registered internal handlers (editKey, commitKey, commitKeys, isLocizeEnabled, requestInitialize, …) without validating event.origin. The pre-patch listener in src/api/postMessage.js gates dispatch on event.data.sender === "i18next-editor-frame" — that value sits inside the attacker-controlled message payload, not the browser-enforced origin. Any web page that could embed or be embedded by a locize-enabled host — an iframe on a third-party page, a window.open-ed victim, a parent frame reaching down — could send a crafted postMessage and trigger the internal handlers. This issue has been patched in version 4.0.21.
- Score
- CVSS 3.1 7.5 High
- Status
- Deferred - security-advisories@github.com
- Published
- 2026-05-08
- Last modified
- 2026-05-08
- Weaknesses
- CWE-346, CWE-79
Affected products
References
- https://github.com/locize/locize/releases/tag/v4.0.21
- https://github.com/locize/locize/security/advisories/GHSA-w937-fg2h-xhq2
