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

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.

Published: 2026-04-04 Last update: 2026-04-22 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-34771 is rated Low Risk (34.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-34771

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-04 0.04%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-34771

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.6 5.9 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]

Weakness enumeration for CVE-2026-34771

GitHub Security Advisory for CVE-2026-34771

GHSA-8337-3p73-46f4 · Severity: high · Ecosystem: npm — Electron: Use-after-free in WebContents fullscreen, pointer-lock, and keyboard-lock permission callbacks

OS Trackers for CVE-2026-34771

vendor priority summary link
redhat high https://access.redhat.com/security/cve/CVE-2026-34771

Affected software / configurations for CVE-2026-34771

Vendor Product Version Raw CPE
electronjs electron < 38.8.6 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron >= 39.0.0, < 39.8.0 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron >= 40.0.0, < 40.7.0 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha1:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha2:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha3:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha4:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha5:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:alpha6:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta1:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta2:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta3:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta4:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta5:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta6:*:*:*:node.js:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta7:*:*:*:node.js:*:*

References for CVE-2026-34771

cvelogic Threat Intelligence