CVE-2026-70601
Prior to 39.8.9, 40.9.2, 41.2.2, and 42.0.0-beta.5, apps that expose Promise-returning functions to web content via contextBridge may be vulnerable to a context isolation bypass.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.24%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.9, 40.9.2, 41.2.2, and 42.0.0-beta.5, apps that expose Promise-returning functions to web content via contextBridge may be vulnerable to a context isolation bypass. Untrusted web content could obtain access to the isolated preload world and, through it, every capability the preload script has. In renderers without a sandbox, or with nodeIntegration enabled, this may escalate to Node.js access. Apps are affected if they expose Promise-returning functions via contextBridge, the standard pattern for wrapping ipcRenderer.invoke, in windows that load untrusted content. This issue is fixed in versions 39.8.9, 40.9.2, 41.2.2, and 42.0.0-beta.5.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N
- EPSS
- 0.24% probability · 16th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-693
- Source
- security-advisories@github.com
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.