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    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-112362",
        "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
        "state": "PUBLISHED",
        "assignerShortName": "openjs",
        "dateReserved": "2026-10-19T14:59:03.468Z",
        "datePublished": "2026-10-27T11:27:59.364Z",
        "dateUpdated": "2026-10-27T11:27:59.364Z"
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                "orgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
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                "dateUpdated": "2026-10-27T11:27:59.364Z"
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            "descriptions": [
                {
                    "lang": "en",
                    "value": "@fastify/express is a Fastify plugin that runs Express middleware inside Fastify. In versions 4.0.5 through 4.0.8, when Fastify runs with the non-default ignoreDuplicateSlashes option enabled, the plugin matches path-scoped Express middleware against a URL whose duplicate-slash normalization has also collapsed the separator after an absolute-form request target's scheme, so Fastify's router resolves the request to the scoped path and runs the handler while the Express layer no longer sees that path. As a result, a request using an absolute-form target can reach a handler on a scoped route such as an admin path while the middleware for authentication, authorization, or rate limiting is skipped. An unauthenticated attacker needs only the non-default ignoreDuplicateSlashes option to be enabled. The issue is fixed in @fastify/express 4.0.9, and users should upgrade to 4.0.9 or later. As a workaround, enforce authentication in a Fastify hook such as preHandler that runs after the router resolves the request, or leave ignoreDuplicateSlashes at its default.",
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                            "value": "@fastify/express is a Fastify plugin that runs Express middleware inside Fastify. In versions 4.0.5 through 4.0.8, when Fastify runs with the non-default ignoreDuplicateSlashes option enabled, the plugin matches path-scoped Express middleware against a URL whose duplicate-slash normalization has also collapsed the separator after an absolute-form request target's scheme, so Fastify's router resolves the request to the scoped path and runs the handler while the Express layer no longer sees that path. As a result, a request using an absolute-form target can reach a handler on a scoped route such as an admin path while the middleware for authentication, authorization, or rate limiting is skipped. An unauthenticated attacker needs only the non-default ignoreDuplicateSlashes option to be enabled. The issue is fixed in @fastify/express 4.0.9, and users should upgrade to 4.0.9 or later. As a workaround, enforce authentication in a Fastify hook such as preHandler that runs after the router resolves the request, or leave ignoreDuplicateSlashes at its default."
                        }
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            ],
            "affected": [
                {
                    "vendor": "@fastify/express",
                    "product": "@fastify/express",
                    "defaultStatus": "unaffected",
                    "versions": [
                        {
                            "versionType": "semver",
                            "status": "affected",
                            "version": "4.0.5",
                            "lessThan": "4.0.9"
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                        {
                            "versionType": "semver",
                            "status": "unaffected",
                            "version": "4.0.9"
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                    ],
                    "packageURL": "pkg:npm/@fastify/express"
                }
            ],
            "references": [
                {
                    "url": "https://github.com/fastify/fastify-express/security/advisories/GHSA-6h42-57hq-9746"
                },
                {
                    "url": "https://cna.openjsf.org/security-advisories.html"
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                    "type": "reporter",
                    "value": "agent-killjoy"
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                {
                    "lang": "en",
                    "type": "remediation developer",
                    "value": "mcollina"
                },
                {
                    "lang": "en",
                    "type": "remediation reviewer",
                    "value": "UlisesGascon"
                }
            ],
            "title": "@fastify/express vulnerable to path-scoped middleware bypass via absolute-form request targets",
            "metrics": [
                {
                    "format": "CVSS",
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                        "baseScore": 9.1,
                        "baseSeverity": "CRITICAL"
                    },
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                            "lang": "en",
                            "value": "GENERAL"
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            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-436",
                            "lang": "en",
                            "description": "CWE-436: Interpretation Conflict",
                            "type": "CWE"
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