{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-6402", "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb", "state": "PUBLISHED", "assignerShortName": "openjs", "dateReserved": "2026-04-15T20:35:29.271Z", "datePublished": "2026-05-12T07:45:21.253Z", "dateUpdated": "2026-05-12T07:45:21.253Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "ce714d77-add3-4f53-aff5-83d477b104bb", "shortName": "openjs", "dateUpdated": "2026-05-12T07:45:21.253Z"}, "descriptions": [{"lang": "en", "value": "webpack-dev-server versions up to and including 5.2.3 are vulnerable to cross-origin source code exposure when serving over a non-potentially trustworthy origin such as plain HTTP. The previous fix relied on the Sec-Fetch-Mode and Sec-Fetch-Site request headers, which browsers omit for non-trustworthy origins, allowing a malicious site to load the bundled source as a script and read it across origins. Impact: an attacker controlling a website visited by a developer running webpack-dev-server can recover the application source code when the dev server runs over HTTP at a guessable host and port. Chromium based browsers from Chrome 142 onward are not affected due to local network access restrictions. Upgrade to webpack-dev-server 5.2.4 or later, which sets Cross-Origin-Resource-Policy: same-origin on responses.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "webpack-dev-server versions up to and including 5.2.3 are vulnerable to cross-origin source code exposure when serving over a non-potentially trustworthy origin such as plain HTTP. The previous fix relied on the Sec-Fetch-Mode and Sec-Fetch-Site request headers, which browsers omit for non-trustworthy origins, allowing a malicious site to load the bundled source as a script and read it across origins. Impact: an attacker controlling a website visited by a developer running webpack-dev-server can recover the application source code when the dev server runs over HTTP at a guessable host and port. Chromium based browsers from Chrome 142 onward are not affected due to local network access restrictions. Upgrade to webpack-dev-server 5.2.4 or later, which sets Cross-Origin-Resource-Policy: same-origin on responses."}]}], "affected": [{"vendor": "webpack-dev-server", "product": "webpack-dev-server", "defaultStatus": "unaffected", "versions": [{"versionType": "semver", "status": "affected", "version": "0", "lessThan": "5.2.4"}, {"versionType": "semver", "status": "unaffected", "version": "5.2.4"}], "packageURL": "pkg:npm/webpack-dev-server"}], "references": [{"url": "https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-79cf-xcqc-c78w"}, {"url": "https://cna.openjsf.org/security-advisories.html"}], "credits": [{"lang": "en", "type": "reporter", "value": "sapphi-red"}, {"lang": "en", "type": "remediation developer", "value": "Ulises Gasc\u00f3n"}, {"lang": "en", "type": "remediation developer", "value": "Sebastian Beltran"}, {"lang": "en", "type": "remediation reviewer", "value": "Alexander Akait"}], "title": "webpack-dev-server vulnerable to cross-origin source code exposure on non-HTTPS origins", "metrics": [{"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N", "baseScore": 5.3, "baseSeverity": "MEDIUM"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-749", "lang": "en", "description": "CWE-749: Exposed Dangerous Method or Function", "type": "CWE"}]}], "x_generator": {"engine": "cve-kit 1.0.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "webpack-dev-server versions up to and including 5.2.3 are vulnerable to cross-origin source code exposure when serving over a non-potentially trustworthy origin such as plain HTTP. The previous fix relied on the Sec-Fetch-Mode and Sec-Fetch-Site request headers, which browsers omit for non-trustworthy origins, allowing a malicious site to load the bundled source as a script and read it across origins. Impact: an attacker controlling a website visited by a developer running webpack-dev-server can recover the application source code when the dev server runs over HTTP at a guessable host and port. Chromium based browsers from Chrome 142 onward are not affected due to local network access restrictions. Upgrade to webpack-dev-server 5.2.4 or later, which sets Cross-Origin-Resource-Policy: same-origin on responses."}], "id": "CVE-2026-6402", "lastModified": "2026-05-12T09:16:55.640", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 1.6, "impactScore": 3.6, "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "type": "Secondary"}]}, "published": "2026-05-12T09:16:55.640", "references": [{"source": "ce714d77-add3-4f53-aff5-83d477b104bb", "url": "https://cna.openjsf.org/security-advisories.html"}, {"source": "ce714d77-add3-4f53-aff5-83d477b104bb", "url": "https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-79cf-xcqc-c78w"}], "sourceIdentifier": "ce714d77-add3-4f53-aff5-83d477b104bb", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-749"}], "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "type": "Secondary"}]}

{}

{"created": "2026-05-12T11:00:07.253441+00:00", "updated": "2026-05-12T11:00:07.253458+00:00", "vendors": []}