Medium severity · published Aug 5, 2026
CVE-2026-70612
Electron: Sandboxed iframes can launch external protocol handlers
5.4
CVSS
0.4%
EPSS
No
On KEV
Description
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, requests to open external protocol URLs from web content did not take iframe sandbox restrictions into account, so a sandboxed iframe could cause an OS-registered external application to be launched. The frame sandbox state was also not made available to the app permission handlers, affecting apps that render untrusted content in sandboxed iframes and grant the openExternal permission by default when no setPermissionRequestHandler is installed. This issue is fixed in 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EL
electron · 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 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-70612
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-70612
Patch
https://github.com/electron/electron/commit/08b9d0a220e267d1a2402a44bdd01a2e9aa320b5
Patch
https://github.com/electron/electron/commit/2764e4c35168855f614876051823db4f58a3714a
Patch
https://github.com/electron/electron/commit/477dcf7afc6550715f9ec5e6f39ee38e5dd7bf39
Patch
https://github.com/electron/electron/commit/c39e3d5687d57434c8d5fe814c5152efd2f631c3
Issue Tracking
https://github.com/electron/electron/pull/50961
Issue Tracking
https://github.com/electron/electron/pull/50962
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