CVE-2026-34765 | Electron named window.open targets not scoped to the opener's browsing context

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5, when a renderer calls window.open() with a target name, Electron did not correctly scope the named-window lookup to the opener's browsing context group. A renderer could navigate an existing child window that was opened by a different, unrelated renderer if both used the same target name. If that existing child was created with more permissive webPreferences (via setWindowOpenHandler's overrideBrowserWindowOptions), content loaded by the second renderer inherits those permissions. Apps are only affected if they open multiple top-level windows with differing trust levels and use setWindowOpenHandler to grant child windows elevated webPreferences such as a privileged preload script. Apps that do not elevate child window privileges, or that use a single top-level window, are not affected. Apps that additionally grant nodeIntegration: true or sandbox: false to child windows (contrary to the security recommendations) may be exposed to arbitrary code execution. This vulnerability is fixed in 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5.

Published: 2026-04-07 Last update: 2026-04-20 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-34765 is rated Low Risk (26.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). 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-2026-34765

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 2026-04-21 0.05% 0.02% -0.03%
2 2026-04-08 — 0.05% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-34765

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.0 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L 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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.8 3.7 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
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.
 2.8 5.9 [email protected]

Weakness enumeration for CVE-2026-34765

GitHub Security Advisory for CVE-2026-34765

GHSA-f3pv-wv63-48x8 · Severity: medium · Ecosystem: npm — Electron: Named window.open targets not scoped to the opener's browsing context

OS Trackers for CVE-2026-34765

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2026-34765

Affected software / configurations for CVE-2026-34765

Vendor Product Version Raw CPE
electronjs electron <= 39.8.4 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron >= 40.0.0, <= 40.8.4 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron >= 41.0.0, < 41.1.0 cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*
electronjs electron 41.2.0 cpe:2.3:a:electronjs:electron:41.2.0:*:*:*:*:node.js:*:*
electronjs electron 42.0.0 cpe:2.3:a:electronjs:electron:42.0.0:alpha1:*:*:*:node.js:*:*
electronjs electron 42.0.0 cpe:2.3:a:electronjs:electron:42.0.0:alpha2:*:*:*:node.js:*:*
electronjs electron 42.0.0 cpe:2.3:a:electronjs:electron:42.0.0:alpha3:*:*:*:node.js:*:*
electronjs electron 42.0.0 cpe:2.3:a:electronjs:electron:42.0.0:alpha4:*:*:*:node.js:*:*

References for CVE-2026-34765

cvelogic Threat Intelligence