CVE-2026-34771
Electron: Use-after-free in WebContents fullscreen, pointer-lock, and keyboard-lock permission callbacks
Description
### Impact Apps that register an asynchronous `session.setPermissionRequestHandler()` may be vulnerable to a use-after-free when handling fullscreen, pointer-lock, or keyboard-lock permission requests. If the requesting frame navigates or the window closes while the permission handler is pending, invoking the stored callback dereferences freed memory, which may lead to a crash or memory corruption. Apps that do not set a permission request handler, or whose handler responds synchronously, are not affected. ### Workarounds Respond to permission requests synchronously, or deny fullscreen, pointer-lock, and keyboard-lock requests if an asynchronous flow is required. ### Fixed Versions * `41.0.0-beta.8` * `40.7.0` * `39.8.0` * `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)
How to fix CVE-2026-34771
To remediate CVE-2026-34771, upgrade the affected package to a fixed version below.
- —upgrade to 38.8.6 or later
Is CVE-2026-34771 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 38.8.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |