CVE-2026-70604 Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads
Remote pages can read sensitive data from custom Electron protocols if CORS is disabled, affecting apps loading untrusted content.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-70604?
CVE-2026-70604 is a high-severity vulnerability in Electronjs Electron, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-942
Which versions are affected by CVE-2026-70604?
8 open source packages ship an affected version, including electron. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
electron npm | All versions | 39.8.10 |
electron npm | All versions | 39.8.10 |
electron npm | From 40.0.0-alpha.1 | 40.9.3 |
electron npm | From 40.0.0-alpha.1 | 40.9.3 |
electron npm | From 41.0.0-alpha.1 | 41.4.0 |
electron npm | From 41.0.0-alpha.1 | 41.4.0 |
2 more packages
electron npm | From 42.0.0-alpha.1 | 42.0.0 |
electron npm | From 42.0.0-alpha.1 | 42.0.0 |
Products include Electronjs Electron.
How do I fix CVE-2026-70604?
Upgrade electron to a fixed version for your release line: 39.8.10, 40.9.3, 41.4.0 or 42.0.0.
Is CVE-2026-70604 being exploited?
There is no known exploitation of CVE-2026-70604 in the wild and no public exploit code.
Other vulnerabilities in Electronjs Electron
- CVE-2017-16151 Chromium Remote Code Execution in electron
- CVE-2018-1000118 Electron protocol handler browser vulnerable to Command Injection
- CVE-2026-34780 Electron: Context Isolation bypass via contextBridge VideoFrame transfer
- CVE-2026-102676 Electron: <webview> can enable Node.js integration in Web Workers despite embedder restrictions
- CVE-2026-102673 Electron drops inherited HTML sandbox restrictions for popups opened through OpenURLFromTab
Sources
Also known as GHSA-v3j7-r9gq-3gjw.