CVE-2026-34773 Electron: Registry key path injection in app.setAsDefaultProtocolClient on Windows
Attackers can hijack protocol handlers by injecting registry paths if apps pass untrusted input to setAsDefaultProtocolClient on Windows.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-34773?
CVE-2026-34773 is a medium-severity path traversal vulnerability in Electronjs Electron, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, on Windows, app.setAsDefaultProtocolClient(protocol) did not validate the protocol name before writing to the registry. Apps that pass untrusted input as the protocol name may allow an attacker to write to arbitrary subkeys under HKCU\Software\Classes\, potentially hijacking existing protocol handlers. Apps are only affected if they call app.setAsDefaultProtocolClient() with a protocol name derived from external or untrusted input. Apps that use a hardcoded protocol name are not affected. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.
Which versions are affected by CVE-2026-34773?
8 open source packages ship an affected version, including electron. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
electron npm | All versions | 38.8.6 |
electron npm | All versions | 38.8.6 |
electron npm | From 39.0.0-alpha.1 | 39.8.1 |
electron npm | From 39.0.0-alpha.1 | 39.8.1 |
electron npm | From 40.0.0-alpha.1 | 40.8.1 |
electron npm | From 40.0.0-alpha.1 | 40.8.1 |
2 more packages
electron npm | From 41.0.0-alpha.1 | 41.0.0 |
electron npm | From 41.0.0-alpha.1 | 41.0.0 |
Products include Electronjs Electron.
How do I fix CVE-2026-34773?
Upgrade electron to a fixed version for your release line: 38.8.6, 39.8.1, 40.8.1 or 41.0.0.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-34773 being exploited?
There is no known exploitation of CVE-2026-34773 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-mwmh-mq4g-g6gr.