CVE-2026-70606 electron CVE debrief

Who should care

Developers using Electron framework, especially those relying on separate sessions to isolate content, and security teams responsible for vulnerability management and ensuring the security of applications built with Electron.

Technical summary

Electron framework vulnerability allows cached response reuse across isolated session partitions in versions before 40.10.6, 41.9.1, 42.5.1, and 43.0.0. This occurs when a custom protocol handler returns a ProtocolResponse with a url and no session, causing Electron to make the upstream request through defaultSession instead of the session that handled the protocol. Apps that use ProtocolResponse.url, omit ProtocolResponse.session, and rely on separate sessions to isolate content are affected. To mitigate, review and update Electron to version 40.10.6, 41.9.1, 42.5.1, or 43.0.0, verify apps using ProtocolResponse.url and omit ProtocolResponse.session, and implement separate sessions to isolate content.

Defensive priority

Electron apps using ProtocolResponse.url without ProtocolResponse.session may be vulnerable to cached response reuse across isolated session partitions.

Recommended defensive actions

• Review and update Electron to version 40.10.6, 41.9.1, 42.5.1, or 43.0.0.
• Verify apps using ProtocolResponse.url and omit ProtocolResponse.session.
• Implement separate sessions to isolate content.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability in Electron framework versions before 40.10.6, 41.9.1, 42.5.1, and 43.0.0. Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 40.10.6, 41.9.1, 42.5.1, and 43.0.0, 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.

Official resources