Electron: Extension tab APIs operate across session boundaries
Published 5 Aug 2026 · Updated 5 Aug 2026
Affected packages
- Affected
- <39.8.8
- Fixed in
- 39.8.8
npm install electron@39.8.8- Affected
- >=40.0.0-alpha.1 <40.9.0
- Fixed in
- 40.9.0
npm install electron@40.9.0- Affected
- >=41.0.0-alpha.1 <41.2.1
- Fixed in
- 41.2.1
npm install electron@41.2.1- Affected
- >=42.0.0-alpha.1 <42.0.0-beta.3
- Fixed in
- 42.0.0-beta.3
npm install electron@42.0.0-beta.3Details
Impact
Extension tab and scripting APIs were not scoped to the extension's own session. A malicious or compromised extension loaded into one session could navigate, script, and read from windows belonging to a different session.
Apps are only affected if they load Chrome extensions via session.loadExtension and rely on separate sessions to isolate that extension from other content. Apps that do not load extensions, or that use a single session, are not affected.
Workarounds
Only load extensions from sources you trust; do not rely on session separation alone to contain an extension.
Fixed Versions
42.0.0-beta.341.2.140.9.039.8.8
For more information
If you have any questions or comments about this advisory, email Electron at [security@electronjs.org](mailto:security@electronjs.org)
Is GHSA-m55f-7gqj-fr98 in any of your client repos?
Checking one package by hand is fine. Checking it across forty client projects is not. NPMscan reads the lockfiles in every GitHub repo you pick, finds each project with an affected electron, and gives you the command that fixes it.
References
Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.