Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
Medium, CVSS 5.9

Electron: ProtocolResponse.url reuses the default session cache instead of the registering session

CVE-2026-70606GHSA-r4w5-6pfg-jxp5

What to do

Vendor fix available. Upgrade each affected package to the fixed version on its release line (electron 43.0.0, 42.5.1, 41.9.1, 40.10.6), redeploy, then verify what is actually installed.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

  • npm electron

    Affected
    >= 43.0.0-alpha.1, < 43.0.0>= 42.0.0-alpha.1, < 42.5.1>= 41.0.0-alpha.1, < 41.9.1>= 40.0.0-alpha.1, < 40.10.6
    Fixed in
    43.0.0, 40.10.6, 41.9.1, 42.5.1

Sources

  • GitHub Advisory Database and maintainer security advisories on GitHub

    GitHub-reviewed advisory GHSA-r4w5-6pfg-jxp5 lists affected ranges: npm electron >=43.0.0-alpha.1 =42.0.0-alpha.1 =41.0.0-alpha.1 =40.0.0-alpha.1 <40.10.6

    VerifiedObserved Structured GitHub Advisory Database record (type=reviewed) from the GitHub REST API.

Severity and exploitation
Exploitation
No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.
CVSS
5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:N
EPSS
  • CVE-2026-70606: 0.26% estimated exploitation activity in the next 30 days; percentile 17.13 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.
Source description

As published by the source; long descriptions are shortened.

Impact When a custom protocol handler returned a ProtocolResponse with a url and no session, Electron made the upstream request through defaultSession instead of the session that handled the protocol. A cached response could then be reused across otherwise isolated session partitions. Apps that use ProtocolResponse.url, omit ProtocolResponse.session, and rely on separate sessions to isolate content are affected. Apps that set an explicit session, or that do not isolate content across sessions, are not affected. Workarounds Set ProtocolResponse.session explicitly so the request uses the intended session's cache. Fixed Versions 43.0.0 42.5.1 41.9.1 40.10.6 For more information If you have any questions or comments about this advisory, email Electron at security@electronjs.org

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 1 · created ·

    Published from ghsa record GHSA-r4w5-6pfg-jxp5

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-70606

Advisory: Electron: ProtocolResponse.url reuses the default session cache instead of the registering session
IDs: CVE-2026-70606, GHSA-r4w5-6pfg-jxp5
Record: https://patchnext.com/advisories/cve-2026-70606 (revision 1, source checked 26 Oct 2026, 13:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: electron 43.0.0, 42.5.1, 41.9.1, 40.10.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm electron: affected >= 43.0.0-alpha.1, < 43.0.0; >= 42.0.0-alpha.1, < 42.5.1; >= 41.0.0-alpha.1, < 41.9.1; >= 40.0.0-alpha.1, < 40.10.6; fixed in 43.0.0, 40.10.6, 41.9.1, 42.5.1

## Suggested inspection (read-only)
- `npm ls electron --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on electron.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-r4w5-6pfg-jxp5 (GitHub-reviewed advisory GHSA-r4w5-6pfg-jxp5 lists affected ranges: npm electron >=43.0.0-alpha.1 =42.0.0-alpha.1 =41.0.0-alpha.1 =40.0.0-alpha.1 <40.10.6)

Commands are suggestions: review each one before running it.

Loading voting…