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Fencer Vulns
medium 6.6

CVE-2026-70602 json

Electron: Extension tab APIs operate across session boundaries

published 2026-08-05 3 mo ago modified 2026-10-08 31 d ago also GHSA-m55f-7gqj-fr98 , EUVD-2026-53435

cvss
6.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 17%
public exploits
0
none known

Summary

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3, extension tab and scripting APIs were not scoped to the extension's own session. A malicious or compromised extension loaded into one session could navigate, script, and read from windows belonging to a different session. Apps are only affected if they load Chrome extensions via session.loadExtension and rely on separate sessions to isolate that extension from other content. This issue is fixed in versions 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3.

Patch / fix

  • npm electron 39.8.8, 40.9.0, 41.2.1, 42.0.0-beta.3
  • electronjs electron 39.8.8, 40.9.0, 41.2.1

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.6 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N
GitHub 3.1 6.6 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N

Affected packages

ecosystem package affected fixed in
npm electron
<39.8.8
>=40.0.0-alpha.1, <40.9.0
>=41.0.0-alpha.1, <41.2.1
>=42.0.0-alpha.1, <42.0.0-beta.3
39.8.8
40.9.0
41.2.1
42.0.0-beta.3

Affected products

  • electron electron

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.