{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-112712",
        "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
        "state": "PUBLISHED",
        "assignerShortName": "openjs",
        "dateReserved": "2026-10-19T17:43:39.048Z",
        "datePublished": "2026-10-20T20:43:48.681Z",
        "dateUpdated": "2026-10-20T20:43:48.681Z"
    },
    "containers": {
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                "orgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
                "shortName": "openjs",
                "dateUpdated": "2026-10-20T20:43:48.681Z"
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            "descriptions": [
                {
                    "lang": "en",
                    "value": "@fastify/middie is the Express-style middleware engine for Fastify. In versions from 9.0.0 through 9.3.5, the use() function joined a path-scoped middleware's mount path to the plugin scope prefix in a way that could diverge from the path Fastify's router serves, most often when the scope prefix ended in a slash, and also for array mount paths and for mount paths written without a leading slash. When the two paths disagreed, the middleware was silently skipped while the route handler still ran, so path-scoped middleware such as authentication, authorization, or rate limiting could be bypassed by a single unauthenticated request. The issue is fixed in @fastify/middie 9.3.6, and users should upgrade to 9.3.6 or later. As a workaround, enforce authorization in a Fastify hook such as preHandler that runs after the router has resolved the request.",
                    "supportingMedia": [
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                            "value": "@fastify/middie is the Express-style middleware engine for Fastify. In versions from 9.0.0 through 9.3.5, the use() function joined a path-scoped middleware's mount path to the plugin scope prefix in a way that could diverge from the path Fastify's router serves, most often when the scope prefix ended in a slash, and also for array mount paths and for mount paths written without a leading slash. When the two paths disagreed, the middleware was silently skipped while the route handler still ran, so path-scoped middleware such as authentication, authorization, or rate limiting could be bypassed by a single unauthenticated request. The issue is fixed in @fastify/middie 9.3.6, and users should upgrade to 9.3.6 or later. As a workaround, enforce authorization in a Fastify hook such as preHandler that runs after the router has resolved the request."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "@fastify/middie",
                    "product": "@fastify/middie",
                    "defaultStatus": "unaffected",
                    "versions": [
                        {
                            "versionType": "semver",
                            "status": "affected",
                            "version": "9.0.0",
                            "lessThan": "9.3.6"
                        },
                        {
                            "versionType": "semver",
                            "status": "unaffected",
                            "version": "9.3.6"
                        }
                    ],
                    "packageURL": "pkg:npm/@fastify/middie"
                }
            ],
            "references": [
                {
                    "url": "https://github.com/fastify/middie/security/advisories/GHSA-5p92-8765-9fv8"
                },
                {
                    "url": "https://cna.openjsf.org/security-advisories.html"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "reporter",
                    "value": "zachariah-mithani"
                },
                {
                    "lang": "en",
                    "type": "remediation developer",
                    "value": "mcollina"
                },
                {
                    "lang": "en",
                    "type": "remediation developer",
                    "value": "UlisesGascon"
                }
            ],
            "title": "@fastify/middie vulnerable to path-scoped middleware bypass via scope prefix mismatch",
            "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"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ]
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-436",
                            "lang": "en",
                            "description": "CWE-436: Interpretation Conflict",
                            "type": "CWE"
                        }
                    ]
                }
            ],
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