Vulnerability in Electron
CVE-2026-34767
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.3, 40.8.3, and 41.0.3, apps that register custom protocol handlers via protocol.handle() / protocol.registerSchemesAsPrivileged() or modify response headers via webRequest.onHeadersReceived may be vulnerable to HTTP response header injection if attacker-controlled input is reflected into a response header name or value. An attacker who can influence a header value may be able to inject additional response headers, affecting cookies, content security policy, or cross-origin access controls. Apps that do not reflect external input into response headers are not affected. This issue has been patched in versions 38.8.6, 39.8.3, 40.8.3, and 41.0.3.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (15.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 15.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000
Affected products
- Electron — versions < 38.8.6, >= 39.0.0-alpha.1, < 39.8.3, >= 40.0.0-alpha.1, < 40.8.3
- Electronjs Electron
Weakness classification (CWE)
References
- github.com/electron/electron/security/advisories/GHSA-4p4r-m79c-wq3v (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-34767?
- CVE-2026-34767 is a medium-severity vulnerability in Electron, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 5.9/10. Published 2026-04-04.
- How severe is CVE-2026-34767?
- Medium severity. CVSS v3 base score is 5.9 out of 10.