What’s Vulnerable › Vulnerabilities

CVE-2026-34771: Electron: Use-after-free in WebContents fullscreen, pointer-lock, and keyboard-lock permission callbacks

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-04 · updated 2026-07-24
• Weakness: CWE-416

Description

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.0, 40.7.0, and 41.0.0-beta.8, 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. This issue has been patched in versions 38.8.6, 39.8.0, 40.7.0, and 41.0.0-beta.8.

Affected products

• electron: before 38.8.6; from 39.0.0 before 39.8.0; from 40.0.0 before 40.7.0; 41.0.0-alpha1, 41.0.0-alpha2, 41.0.0-alpha3, 41.0.0-alpha4, 41.0.0-alpha5, 41.0.0-alpha6 (+7) — fixed in 38.8.6, 39.8.0, 40.7.0

How to fix

Upgrade to a fixed version: electron 38.8.6, 39.8.0, 40.7.0. Check the vendor advisory for mitigations.

References

• https://github.com/electron/electron/security/advisories/GHSA-8337-3p73-46f4
• https://access.redhat.com/security/cve/CVE-2026-34771
• https://bugzilla.redhat.com/show_bug.cgi?id=2454995
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34771.json

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