Context isolation bypass via nested unserializable return value in Electron

Summary

Electron is a framework which lets you write cross-platform desktop applications using JavaScript, HTML and CSS. Electron apps using `contextIsolation` and `contextBridge` are affected. This is a context isolation bypass, meaning that code running in the main world context in the renderer can reach into the isolated Electron context and perform privileged actions. This issue is only exploitable if an API exposed to the main world via `contextBridge` can return an object or array that contains a javascript object which cannot be serialized, for instance, a canvas rendering context. This would normally result in an exception being thrown `Error: object could not be cloned`. The app side workaround is to ensure that such a case is not possible. Ensure all values returned from a function exposed over the context bridge are supported. This issue has been fixed in versions `25.0.0-alpha.2`, `24.0.1`, `23.2.3`, and `22.3.6`.

Timeline

1. Sep 6, 2023, 8:13 PM UTCCVE published
2. Sep 26, 2024, 2:44 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Sep 26, 2024, 3:12 PM UTCRecord last updated

Affected versions

• electron electron

  fixed in 22.3.6; From 23.0.0 · fixed in 23.2.3; From 24.0.0 · fixed in 24.0.1; From 25.0.0-alpha.1 · fixed in 25.0.0-alpha.2

• electronnpm

  fixed in 22.3.6

• electronnpm

  From 23.0.0-alpha.1 · fixed in 23.2.3

• electronnpm

  From 24.0.0-alpha.1 · fixed in 24.0.1

• electronnpm

  From 25.0.0-alpha.1 · fixed in 25.0.0-alpha.2

References 2