MediumGHSA-3c8v-cfp5-9885CVE-2026-34776

Electron: Out-of-bounds read in second-instance IPC on macOS and Linux

Published 3 Apr 2026 · Updated 6 Apr 2026

Affected packages

electronnpm

Affected: <38.8.6
Fixed in: 38.8.6

Update to the fixed version for your release line, for example:npm install electron@38.8.6

electronnpm

Affected: >=39.0.0-alpha.1 <39.8.1
Fixed in: 39.8.1

Update to the fixed version for your release line, for example:npm install electron@39.8.1

electronnpm

Affected: >=40.0.0-alpha.1 <40.8.1
Fixed in: 40.8.1

Update to the fixed version for your release line, for example:npm install electron@40.8.1

electronnpm

Affected: >=41.0.0-alpha.1 <41.0.0
Fixed in: 41.0.0

Update to the fixed version for your release line, for example:npm install electron@41.0.0

Details

Impact

On macOS and Linux, apps that call app.requestSingleInstanceLock() were vulnerable to an out-of-bounds heap read when parsing a crafted second-instance message. Leaked memory could be delivered to the app's second-instance event handler.

This issue is limited to processes running as the same user as the Electron app.

Apps that do not call app.requestSingleInstanceLock() are not affected. Windows is not affected by this issue.

Workarounds

There are no app side workarounds, developers must update to a patched version of Electron.

Fixed Versions

41.0.0
40.8.1
39.8.1
38.8.6

For more information

If there are any questions or comments about this advisory, please email [security@electronjs.org](mailto:security@electronjs.org)

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.