CVE-2026-14631

webpack-dev-server versions 5.2.5 and earlier terminate the whole Node.js process when an unauthenticated peer sends either a normal HTTP request with a malformed Host header or a WebSocket upgrade to the default /ws endpoint with a malformed Origin header. The malformed value causes an uncaught exception in the host-validation path and crashes the dev server. Impact is limited to availability of the development server, no data disclosure, no code execution. Patches: upgrade to webpack-dev-server 5.2.6. Workarounds: keep the dev server bound to localhost (the default) and do not expose it to untrusted networks.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://cna.openjsf.org/security-advisories.html	Third Party Advisory
https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgj	Mitigation Vendor Advisory Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:webpack.js:webpack-dev-server:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-03 18:16

Updated : 2026-07-07 15:08

NVD link : CVE-2026-14631

Mitre link : CVE-2026-14631

CVE.ORG link : CVE-2026-14631

JSON object : View

Products Affected

webpack.js

webpack-dev-server

CWE

CWE-20

Improper Input Validation

CWE-248

Uncaught Exception

{"id": "CVE-2026-14631", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-14631", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-07-06T15:54:04.567228Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 3.9}]}, "affected": [{"source": "ce714d77-add3-4f53-aff5-83d477b104bb", "affectedData": [{"vendor": "webpack-dev-server", "product": "webpack-dev-server", "versions": [{"status": "affected", "version": "0", "lessThan": "5.2.6", "versionType": "semver"}, {"status": "unaffected", "version": "5.2.6", "versionType": "semver"}], "packageURL": "pkg:npm/webpack-dev-server", "defaultStatus": "unaffected"}]}], "published": "2026-07-03T18:16:24.687", "references": [{"url": "https://cna.openjsf.org/security-advisories.html", "tags": ["Third Party Advisory"], "source": "ce714d77-add3-4f53-aff5-83d477b104bb"}, {"url": "https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgj", "tags": ["Mitigation", "Vendor Advisory", "Patch"], "source": "ce714d77-add3-4f53-aff5-83d477b104bb"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-248"}]}], "descriptions": [{"lang": "en", "value": "webpack-dev-server versions 5.2.5 and earlier terminate the whole Node.js process when an unauthenticated peer sends either a normal HTTP request with a malformed Host header or a WebSocket upgrade to the default /ws endpoint with a malformed Origin header. The malformed value causes an uncaught exception in the host-validation path and crashes the dev server. Impact is limited to availability of the development server, no data disclosure, no code execution. Patches: upgrade to webpack-dev-server 5.2.6. Workarounds: keep the dev server bound to localhost (the default) and do not expose it to untrusted networks."}], "lastModified": "2026-07-07T15:08:59.667", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:webpack.js:webpack-dev-server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "18354AA3-AA9C-44CC-AC11-E305120D5261", "versionEndExcluding": "5.2.6"}], "operator": "OR"}]}], "sourceIdentifier": "ce714d77-add3-4f53-aff5-83d477b104bb"}