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Fencer Intel
medium 6.0

CVE-2026-70603 json

Electron: shell.openPath path validation bypass via embedded null byte

published 3mo ago modified 8d ago also EUVD-2026-53436 , GHSA-5c9j-mhmv-5xgx

cvss
6.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.6, 40.9.0, 41.1.1, and 42.0.0-beta.1, shell.openPath() did not reject paths containing embedded null bytes. Apps that perform string-only validation of file paths, for example checking the file extension, before passing them to shell.openPath() could be bypassed, allowing an attacker-controlled path to open a different file than the one that passed validation. Apps are only affected if they pass paths derived from untrusted input to shell.openPath() and rely on string-based validation without a filesystem check. This issue is fixed in versions 39.8.6, 40.9.0, 41.1.1, and 42.0.0-beta.1.

Patch / fix

  • npm electron 39.8.6, 40.9.0, 41.1.1, 42.0.0-beta.1
  • atom electron 39.8.6, 40.9.0, 41.1.1, 42.0.0-beta.1
  • electronjs electron 39.8.6, 40.9.0, 41.1.1, 42.0.0-beta.1

Is CVE-2026-70603 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
3mo ago

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 6.0 CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
GitHub 3.1 6.0 CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm electron
>=42.0.0-alpha.1, <42.0.0-beta.1
>=41.0.0-alpha.1, <41.1.1
>=40.0.0-alpha.1, <40.9.0
<39.8.6
42.0.0-beta.1
41.1.1
40.9.0
39.8.6

Affected products

  • electron electron

Classification

Weakness
  • CWE-20 Improper Input Validation
  • CWE-158 Improper Neutralization of Null Byte or NUL Character

References

Sources

Fencer Intel 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.

The maintainers of electron/electron published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.