Cyber Resilience

CVE-2026-41886

High

Published: 08 May 2026

Published
08 May 2026
Modified
13 May 2026
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:L
EPSS Score 0.0002 4.8th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-41886 is a high-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Drive-by Compromise (T1189); ranked at the 4.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
Why these techniques?

PostMessage origin bypass (CWE-346) in browser SDK directly enables drive-by client-side JS execution and XSS (CWE-79) via crafted cross-origin messages.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2026-28109Shared CWE-79
CVE-2024-53965Shared CWE-79
CVE-2025-50128Shared CWE-79
CVE-2025-25132Shared CWE-79
CVE-2026-25438Shared CWE-79
CVE-2025-69053Shared CWE-79
CVE-2026-25383Shared CWE-79
CVE-2025-70846Shared CWE-79
CVE-2026-42524Shared CWE-79
CVE-2026-42457Shared CWE-79

Affected Assets

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-346

Requires unique identification of the service before communications, addressing failures to validate the origin of the interaction.

addresses: CWE-346

Trusted path establishment enforces validation that the communication originates from and reaches only the intended trusted system components.

addresses: CWE-346

Enforces validation of the true origin of DNS responses via signatures and chain-of-trust mechanisms.

addresses: CWE-346

Enforces origin validation of name/address data, eliminating reliance on unverified or impersonated DNS sources.

addresses: CWE-346

Mandates origin validation so that only legitimate endpoints can continue the authenticated session.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References