CVE record
CVE-2026-70604
Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.10, 40.9.3, 41.4.0, and 42.0.0, a custom scheme registered with supportFetchAPI: true but without corsEnabled: true was not subject to CORS enforcement. A page loaded from a remote origin could therefore fetch() or XMLHttpRequest that scheme cross-origin and read the full response body, rather than the read being blocked. Apps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. This issue is fixed in versions 39.8.10, 40.9.3, 41.4.0, and 42.0.0.
CVE evidence
Known exploitation
Not listed in fetched KEV catalog
Absence from the fetched catalog does not establish that exploitation has not occurred.
Severity
high
CVSS 7.4 ยท CVSS_V3
Affected packages
1
Supported package records returned by OSV. Vendor and product names are not used to infer matches.
OSV package mapping
Affected open-source packages
| Package | Ecosystem | Fixed versions |
|---|---|---|
| electron | npm | 42.0.0, 41.4.0, 40.9.3, 39.8.10 |