CVE-2026-70612
Electron: Sandboxed iframes can launch external protocol handlers
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Electron: Sandboxed iframes can launch external protocol handlers
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.
- Record
CVE-2026-70612- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
EUVDEUVD-2026-53546
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.
- Record
EUVD-2026-53546- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-p2rr-rvmm-c5fp
Electron: Sandboxed iframes can launch external protocol handlers
Impact
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's sandbox state was also not made available to the app's permission handlers.
Apps are only affected if they render untrusted content in sandboxed iframes and grant the openExternal permission (granted by default when no setPermissionRequestHandler is installed). Apps whose permission handler denies openExternal for untrusted content are not affected.
Workarounds
Install a setPermissionRequestHandler that denies the openExternal permission for untrusted content.
Fixed Versions
42.0.0-beta.341.2.140.9.039.8.8
For more information
If you have any questions or comments about this advisory, email Electron at [email protected]
- Record
GHSA-p2rr-rvmm-c5fp- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-70612- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
OSV
Electron: Sandboxed iframes can launch external protocol handlers
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.
- Record
CVE-2026-70612- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
OSVGHSA-p2rr-rvmm-c5fp
Electron: Sandboxed iframes can launch external protocol handlers
Impact
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's sandbox state was also not made available to the app's permission handlers.
Apps are only affected if they render untrusted content in sandboxed iframes and grant the openExternal permission (granted by default when no setPermissionRequestHandler is installed). Apps whose permission handler denies openExternal for untrusted content are not affected.
Workarounds
Install a setPermissionRequestHandler that denies the openExternal permission for untrusted content.
Fixed Versions
42.0.0-beta.341.2.140.9.039.8.8
For more information
If you have any questions or comments about this advisory, email Electron at [email protected]
- Record
GHSA-p2rr-rvmm-c5fp- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-70612 is a medium vulnerability (CVSS 5.4) in Electron, published August 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. Fixed in electron 39.8.8.
References
github.com/electron/electron/security/advisories/GHSA-p2rr-rvmm-c5fp
Show 11 moreShow less
nvd.nist.gov/vuln/detail/CVE-2026-70612