CVE-2026-70604 json
Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads
published 2026-08-05 3 mo ago modified 2026-10-08 31 d ago also GHSA-v3j7-r9gq-3gjw , EUVD-2026-53440
- cvss
- 7.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 29%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm electron 39.8.10, 40.9.3, 41.4.0, 42.0.0
- electronjs electron 39.8.10, 40.9.3, 41.4.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3 mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N |
| GitHub | 3.1 | 7.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | electron | >=42.0.0-alpha.1, <42.0.0 >=41.0.0-alpha.1, <41.4.0 >=40.0.0-alpha.1, <40.9.3 <39.8.10 |
42.0.0 41.4.0 40.9.3 39.8.10 |
Affected products
- electron electron
Classification
- Weakness
-
- CWE-942 Permissive Cross-domain Security Policy with Untrusted Domains
References
-
github.com
/electron/electron/security/advisories/GHSA-v3j7-r9gq-3gjw
web, vendor-advisory
-
github.com
/electron/electron
package
Sources
- CVE List CVE-2026-70604
- GitHub Advisory GHSA-v3j7-r9gq-3gjw
- NVD CVE-2026-70604
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