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Fencer Vulns
medium 5.9

CVE-2026-34767 json

Electron: HTTP Response Header Injection in custom protocol handlers and webRequest

published 2026-04-03 7 mo ago modified 2026-07-24 3 mo ago also EUVD-2026-18933 , GHSA-4p4r-m79c-wq3v

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

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.

Patch / fix

  • npm electron 38.8.6, 39.8.3, 40.8.3, 41.0.3
  • atom electron 38.8.6, 39.8.3, 40.8.3, 41.0.3
  • electronjs electron 38.8.6, 39.8.3, 40.8.3, 41.0.3

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-34767 updated cvss 5.9

electron: Electron: HTTP Response Header Injection via attacker-controlled input

  • Red Hat Build of Podman Desktop podman-desktop-macos-1-0, podman-desktop-windows-1-0 Red Hat Build of Podman Desktop - Tech Preview rhdesktop/rh-podman-desktop-ext-openshift-local-rhel10
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
7 mo ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N
GitHub 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm electron
<38.8.6
>=39.0.0-alpha.1, <39.8.3
>=40.0.0-alpha.1, <40.8.3
>=41.0.0-alpha.1, <41.0.3
38.8.6
39.8.3
40.8.3
41.0.3

Affected products

  • electron electron

Classification

Weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component
  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers

References

Sources

Fencer Vulns 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.

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