CVE Intelligence
Medium

CVE-2026-102673 — Electron drops inherited HTML sandbox restrictions for popups opened through OpenURLFromTab

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 41.10.4, 42.5.2, and 43.0.0, popups opened from a sandboxed iframe through Electron's OpenURLFromTab navigation path, including links using target="_blank" or a middle-click, did not receive the inherited HTML sandbox restrictions. An untrusted iframe using the allow-scripts allow-popups configuration could therefore open a popup with the embedding application's full origin, exposing that origin's cookies, storage, and same-origin scripting capabilities. Applications that do not embed untrusted content in sandboxed iframes are not affected. This issue is fixed in versions 41.10.4, 42.5.2, and 43.0.0.

Published Sep 29, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.1% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.15%
ahead of 4% of scored CVEs · Oct 14, 2026
Affects
Electron
Electron
CVSS base
6.1
Medium · 4 source(s)
Prioritization reference: 8.2 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)
  • Npm Electron: fixed in version 41.10.4 — github.com (GitHub Security Advisories)
  • Npm Electron: fixed in version 42.5.2 — github.com (GitHub Security Advisories)
  • Npm Electron: fixed in version 43.0.0 — github.com (GitHub Security Advisories)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Electron Electron, Electronjs Electron, Npm Electron).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Electron Electron version >= 43.0.0-alpha.1, < 43.0.0version >= 42.0.0-alpha.1, < 42.5.2version < 41.10.4 Vulnerable CVE Program (cve.org) e CISA ADP
Electronjs Electron ≥ 40.0.0 and < 40.9.0version 42.0.0-beta2version 42.0.0-beta1version 42.0.0-alpha6version 42.0.0-alpha5version 42.0.0-alpha4version 42.0.0-alpha3version 42.0.0-alpha2
and 3 more version 42.0.0-alpha1≥ 41.0.0 and ≤ 41.2.1< 39.8.8
Vulnerable NIST National Vulnerability Database
Npm Electron < 41.10.4≥ 42.0.0-alpha.1 and < 42.5.2≥ 43.0.0-alpha.1 and < 43.0.0 Vulnerable GitHub Security Advisories

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.2 CVSS 3.1 High 2.8 4.7 security-advisories@github.com via NIST National Vulnerability Database
8.2 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.2 CVSS 3.1 High — — GitHub_M via CVE Program (cve.org) e CISA ADP
6.1 CVSS 3.1 Medium 2.8 2.7 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.2 (security-advisories@github.com via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-346

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Fix documented
    Oct 15, 2026 · GitHub Security Advisories
  • Affected products added · npm/electron
    Oct 15, 2026 · GitHub Security Advisories
  • Affected products added · electron/electron
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • Fix documented
    Oct 15, 2026 · NIST National Vulnerability Database
  • Affected products added · electronjs/electron
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVSS changed · 6.1
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · Alertas do Telegram
  • CVE published
    Sep 29, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 15, 2026 – Oct 15, 2026
  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

9 on the record

Elsewhere on this site

Electron
every CVE for this vendor
CWE-346
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-102672 Electron: Local race condition in Squirrel.Mac update installation on macOS 2d
  • CVE-2026-102677 Electron: Sandboxed preload code cache can be poisoned by a compromised renderer 16d
  • CVE-2026-102676 Electron: <webview> can enable Node.js integration in Web Workers despite embedder restrictions 16d
  • CVE-2026-102674 Electron: Windows opened from a sandboxed top-level document do not inherit its sandbox restrictions 16d
  • CVE-2026-70612 Electron: Sandboxed iframes can launch external protocol handlers Aug 5, 2026
  • CVE-2026-70610 Electron: contextBridge object copy honors prototype setters Aug 5, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-102673 is "Electron drops inherited HTML sandbox restrictions for popups opened through OpenURLFromTab", rated Medium. It affects Electron (Electron); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.1 describes technical severity. EPSS 0.15% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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