{"id":"CVE-2026-70604","aliases":["GHSA-v3j7-r9gq-3gjw"],"url":"https://o3.security/vulnerability/CVE-2026-70604","summary":"Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads","details":"### Impact\nA 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.\n\nApps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. Apps that set `corsEnabled: true`, or that do not load untrusted content, are not affected.\n\n### Workarounds\nSet `corsEnabled: true` on schemes that must enforce CORS, and validate the request `Origin` in your protocol handler before returning sensitive data.\n\n### Fixed Versions\n* `42.0.0`\n* `41.4.0`\n* `40.9.3`\n* `39.8.10`\n\n### For more information\nIf you have any questions or comments about this advisory, email Electron at [security@electronjs.org](mailto:security@electronjs.org)","published":"2026-08-05T15:59:24.043Z","modified":"2026-10-28T02:31:11.532703316Z","cvss":{"score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"electron","fixedVersion":"42.0.0"},{"ecosystem":"npm","name":"electron","fixedVersion":"41.4.0"},{"ecosystem":"npm","name":"electron","fixedVersion":"40.9.3"},{"ecosystem":"npm","name":"electron","fixedVersion":"39.8.10"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/70xxx/CVE-2026-70604.json"},{"type":"ADVISORY","url":"https://github.com/electron/electron/security/advisories/GHSA-v3j7-r9gq-3gjw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-70604"},{"type":"PACKAGE","url":"https://github.com/electron/electron"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:31:11.532703316Z"}}