CVE-2026-34774 | Electron: Use-after-free in offscreen child window paint callback

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 39.8.1, 40.7.0, and 41.0.0, apps that use offscreen rendering and allow child windows via window.open() may be vulnerable to a use-after-free. If the parent offscreen WebContents is destroyed while a child window remains open, subsequent paint frames on the child dereference freed memory, which may lead to a crash or memory corruption. Apps are only affected if they use offscreen rendering (webPreferences.offscreen: true) and their setWindowOpenHandler permits child windows. Apps that do not use offscreen rendering, or that deny child windows, are not affected. This issue has been patched in versions 39.8.1, 40.7.0, and 41.0.0.

Published: 2026-04-04 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-34774 is rated Moderate Risk (41.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.34%). Review affected assets and schedule remediation.

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-2026-34774

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 2026-06-15 0.02% 0.34% +0.32%
2 2026-04-21 0.06% 0.02% -0.04%
3 2026-04-09 — 0.06% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-34774

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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.
 2.2 5.9 [email protected]

Weakness enumeration for CVE-2026-34774

GitHub Security Advisory for CVE-2026-34774

GHSA-532v-xpq5-8h95 · Severity: high · Ecosystem: npm — Electron: Use-after-free in offscreen child window paint callback

OS Trackers for CVE-2026-34774

vendor priority summary link
redhat high — https://access.redhat.com/security/cve/CVE-2026-34774

Affected software / configurations for CVE-2026-34774

Vendor Product Version Raw CPE
electronjs electron < 39.8.1 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:*:*
electronjs electron 41.0.0 cpe:2.3:a:electronjs:electron:41.0.0:beta8:*:*:*:node.js:*:*

References for CVE-2026-34774

cvelogic Threat Intelligence