CVE-2026-123872

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-123872", "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb", "state": "PUBLISHED", "assignerShortName": "openjs", "dateReserved": "2026-11-06T16:19:31.993Z", "datePublished": "2026-11-11T18:30:25.193Z", "dateUpdated": "2026-11-11T18:30:25.193Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "ce714d77-add3-4f53-aff5-83d477b104bb", "shortName": "openjs", "dateUpdated": "2026-11-11T18:30:25.193Z"}, "title": "Node.js is vulnerable to a client certificate authentication bypass via TLS 1.2 renegotiation servername change", "descriptions": [{"lang": "en", "value": "A client certificate authentication bypass in Node.js TLS lets a client change the servername during TLS 1.2 renegotiation to reach endpoints it was not authorized for. On a server that applies different client-certificate policies per hostname, for example stricter admin-only client-cert auth on one host and ordinary client-cert auth on another, a client that authenticates for a permitted host can renegotiate the TLS 1.2 connection under a different servername and carry its existing authentication to the protected host, bypassing the stricter policy. This vulnerability affects Node.js 26.x, 24.x, and 22.x.", "supportingMedia": [{"type": "text/markdown", "base64": false, "value": "A client certificate authentication bypass in Node.js TLS lets a client change the `servername` during TLS 1.2 renegotiation to reach endpoints it was not authorized for. On a server that applies different client-certificate policies per hostname, for example stricter admin-only client-cert auth on one host and ordinary client-cert auth on another, a client that authenticates for a permitted host can renegotiate the TLS 1.2 connection under a different `servername` and carry its existing authentication to the protected host, bypassing the stricter policy. This vulnerability affects Node.js 26.x, 24.x, and 22.x."}]}], "credits": [{"lang": "en", "value": "pimterry", "type": "reporter"}, {"lang": "en", "value": "pimterry", "type": "remediation developer"}, {"lang": "en", "value": "aduh95", "type": "coordinator"}], "affected": [{"vendor": "nodejs", "product": "node", "defaultStatus": "unaffected", "versions": [{"version": "0.0.0", "status": "affected", "lessThan": "22.23.5", "versionType": "semver"}, {"version": "23.0.0", "status": "affected", "lessThan": "24.22.3", "versionType": "semver"}, {"version": "25.0.0", "status": "affected", "lessThan": "26.13.1", "versionType": "semver"}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-287", "description": "Improper Authentication - Generic"}]}], "metrics": [{"format": "CVSS", "cvssV3_0": {"version": "3.0", "vectorString": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "baseScore": 8.1, "baseSeverity": "HIGH"}}], "references": [{"url": "https://nodejs.org/en/blog/vulnerability/november-2026-security-releases", "tags": ["vendor-advisory"]}, {"url": "https://cna.openjsf.org/security-advisories.html"}], "x_generator": {"engine": "nodejs-private/security-release publish-cves"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "node", "vendor": "nodejs", "versions": [{"lessThan": "22.23.5", "status": "affected", "version": "0.0.0", "versionType": "semver"}, {"lessThan": "24.22.3", "status": "affected", "version": "23.0.0", "versionType": "semver"}, {"lessThan": "26.13.1", "status": "affected", "version": "25.0.0", "versionType": "semver"}]}], "source": "ce714d77-add3-4f53-aff5-83d477b104bb"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A client certificate authentication bypass in Node.js TLS lets a client change the servername during TLS 1.2 renegotiation to reach endpoints it was not authorized for. On a server that applies different client-certificate policies per hostname, for example stricter admin-only client-cert auth on one host and ordinary client-cert auth on another, a client that authenticates for a permitted host can renegotiate the TLS 1.2 connection under a different servername and carry its existing authentication to the protected host, bypassing the stricter policy. This vulnerability affects Node.js 26.x, 24.x, and 22.x."}], "id": "CVE-2026-123872", "lastModified": "2026-11-12T19:02:35.830", "metrics": {"cvssMetricV30": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 8.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "version": "3.0"}, "exploitabilityScore": 2.8, "impactScore": 5.2, "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "type": "Secondary"}]}, "published": "2026-11-11T19:17:34.270", "references": [{"source": "ce714d77-add3-4f53-aff5-83d477b104bb", "url": "https://cna.openjsf.org/security-advisories.html"}, {"source": "ce714d77-add3-4f53-aff5-83d477b104bb", "url": "https://nodejs.org/en/blog/vulnerability/november-2026-security-releases"}], "sourceIdentifier": "ce714d77-add3-4f53-aff5-83d477b104bb", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-287"}], "source": "ce714d77-add3-4f53-aff5-83d477b104bb", "type": "Secondary"}]}

{"bugzilla": {"description": "nodejs: Node.js: Client certificate authentication bypass via TLS renegotiation", "id": "2571847", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2571847"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "status": "draft"}, "cwe": "CWE-295", "details": ["A flaw was found in Node.js. An authenticated remote attacker can bypass client certificate authentication policies on servers configuring different security requirements per hostname. By renegotiating an established Transport Layer Security (TLS) connection and changing the target server name, the attacker can carry forward their existing authenticated session to gain unauthorized access to restricted endpoints."], "mitigation": {"lang": "en:us", "value": "Enforce TLS 1.3 to eliminate TLS renegotiation, or isolate virtual host policies using an upstream reverse proxy.\nTo enforce TLS 1.3 across Node.js services without application code modifications, configure the minimum TLS version using the NODE_OPTIONS environment variable:\n```\nexport NODE_OPTIONS=\"--tls-min-v1.3\"\n```\nFor systemd-managed Node.js applications, configure the environment variable within the unit configuration:\n```\n[Service]\nEnvironment=\"NODE_OPTIONS=--tls-min-v1.3\"\n```\nApply the configuration by reloading systemd and restarting the target service:\n```\nsystemctl daemon-reload\nsystemctl restart <service_name>\n```\nCaveats:\nEnforcing TLS 1.3 prevents clients that support only TLS 1.2 or earlier from establishing connections. Applying systemd configuration changes and restarting the service will cause a momentary service interruption. Alternatively, if TLS 1.2 support must be retained, terminate TLS connections at a reverse proxy configured to bind differing mutual TLS authentication domains to separate listening addresses or ports."}, "name": "CVE-2026-123872", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Will not fix", "package_name": "nodejs20", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "nodejs22", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "nodejs24", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Will not fix", "package_name": "nodejs25", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "nodejs26", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-11-11T18:30:25Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-123872\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-123872\nhttps://cna.openjsf.org/security-advisories.html\nhttps://nodejs.org/en/blog/vulnerability/november-2026-security-releases"], "statement": "This vulnerability is rated as an Important severity flaw because an authenticated attacker can circumvent host-level access controls and reach privileged virtual host endpoints over an existing connection. Exploitation requires non-default architectures where a Node.js process directly handles TLS termination across multi-tenant domains with heterogeneous mutual TLS policies using TLS 1.2. Deployments where TLS is terminated by front-end reverse proxies, ingress routers, or environments utilizing TLS 1.3 exclusively are not exposed to this renegotiation issue.", "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0.0.0,22.23.5)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[23.0.0,24.22.3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[25.0.0,26.13.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "node", "source": "cna", "vendor": "nodejs"}, "product": "nodejs", "vendor": "nodejs"}], "created": "2026-11-12T13:45:03.648310+00:00", "updated": "2026-11-12T18:30:06.843666+00:00", "vendors": ["nodejs", "nodejs$PRODUCT$nodejs"]}