Vulnerabilities in pkg:npm/@nestjs/platform-fastify
PACKAGEGHSA-9c5c-9qcx-q35q is a HIGH (CVSS 7.4) path-scoped middleware bypass vulnerability (CWE-436: Interpretation Conflict) affecting @nestjs/platform-fastify libraries in the npm ecosystem. The issue involves path-scoped middleware bypass via absolute-form request targets. Remediation is available by upgrading affected packages to version 11.2.4, 12.0.2.
pkg:npm/@nestjs/platform-fastify
Vulnerability advisories affecting package pkg:npm/@nestjs/platform-fastify. Select an advisory below to view technical details or fixes.
| Advisory ID | CVE / NVD | Severity | Summary |
|---|---|---|---|
| GHSA-9c5c-9qcx-q35q | - | HIGH | @nestjs/platform-fastify: Path-scoped middleware bypass via absolute-form request targets |
| GHSA-6v32-fjc9-9qf6 | CVE-2026-54281 | HIGH | Nest: Middleware Bypass on Fastify via Trailing Slash |
| GHSA-wf42-42fg-fg84 | CVE-2026-33011 | HIGH | Nest Fastify HEAD Request Middleware Bypass |
| GHSA-r4wm-x892-vjmx | CVE-2026-2293 | HIGH | Nest has a Fastify URL Encoding Middleware Bypass |
| GHSA-7q64-3rg2-h9pf | - | HIGH | Duplicate Advisory: Nest has a Fastify URL Encoding Middleware Bypass |
| GHSA-8wpr-639p-ccrj | CVE-2025-69211 | MODERATE | Nest has a Fastify URL Encoding Middleware Bypass (TOCTOU) |
GHSA-9c5c-9qcx-q35q at a Glance
Security Impact
CVSS: 7.4
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N).
How to Fix GHSA-9c5c-9qcx-q35q
To remediate this vulnerability, upgrade all affected @nestjs/platform-fastify dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install @nestjs/platform-fastify@11.2.4
npm install @nestjs/platform-fastify@12.0.2
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls @nestjs/platform-fastify
How to Check if You Are Affected
To determine whether your Node.js application is affected by GHSA-9c5c-9qcx-q35q, inspect your project dependencies using npm:
npm ls @nestjs/platform-fastify
Analyze the terminal output to locate any version of @nestjs/platform-fastify in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 11.2.4), your application is affected.
Note: The npm ls @nestjs/platform-fastify command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-436: Interpretation Conflict, where product a handles inputs or steps differently than product b, which causes a to perform incorrect actions based on its perception of b's state. In @nestjs/platform-fastify, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
GHSA-9c5c-9qcx-q35q Affected @nestjs/platform-fastify Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
@nestjs/platform-fastify
|
npm |
< 11.2.4
|
11.2.4
|
|
@nestjs/platform-fastify
|
npm |
≥ 12.0.0
< 12.0.2
|
12.0.2
|
References
Frequently Asked Questions
What is GHSA-9c5c-9qcx-q35q?
Which @nestjs/platform-fastify versions are affected?
What version fixes GHSA-9c5c-9qcx-q35q?
Is @nestjs/platform-fastify affected?
What is the CVSS score of GHSA-9c5c-9qcx-q35q?
What CWE is associated with GHSA-9c5c-9qcx-q35q?
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Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-9c5c-9qcx-q35q",
"modified" : "2026-09-30T14:41:39Z",
"published" : "2026-09-30T14:41:39Z",
"aliases" : [ ],
"summary" : "@nestjs/platform-fastify: Path-scoped middleware bypass via absolute-form request targets",
"details" : "| Field | Value |\n| --- | --- |\n| Ecosystem | npm |\n| Package | `@nestjs/platform-fastify` |\n| Affected versions | `>= 12.0.0, < 12.0.2` and `< 11.2.4` |\n| Patched versions | `12.0.2` and `11.2.4` (upgrade to `12.0.3` / `11.2.5`) |\n\n### Summary\n\nOn the Fastify adapter, an HTTP request that uses an **absolute-form request target** (`GET http://host/path HTTP/1.1`\ninstead of `GET /path HTTP/1.1`) reaches the route handler without running the path-scoped Nest middleware bound to\nthat route. Applications that enforce authentication or authorization in middleware execute the protected handler\nwith those checks skipped.\n\n### Impact\n\nAny application that\n\n- uses `@nestjs/platform-fastify`, and\n- binds middleware to specific paths via `MiddlewareConsumer.forRoutes(...)` or `.exclude(...)`, and\n- is reachable by a client that controls the raw request line.\n\nNode's HTTP server accepts absolute-form targets, so no special server configuration is needed. Exposure is reduced\nwhen a reverse proxy in front of the application rewrites the request target to origin-form, which most do.\n\nWhere the bypassed middleware performs authentication or authorization, the result is an authentication or\nauthorization bypass. Where it performs logging, rate limiting or body handling, those are silently skipped instead.\n\n### Details\n\nFastify's router (`find-my-way`) resolves an absolute-form target to its path before matching, so the route handler\nis dispatched normally. Two places on the middleware side matched against the **raw** request target instead:\n\n1. The bundled copy of the `@fastify/middie` engine at `packages/platform-fastify/adapters/middie/fastify-middie.ts`.\n NestJS carried this fork to apply an earlier path-decoding fix and it did not track the upstream absolute-form fix\n released in `@fastify/middie@9.3.4`.\n2. `FastifyAdapter`'s own re-check in `createMiddlewareFactory()`, which tests the middleware path regexp against\n `req.originalUrl`.\n\nBoth normalized and percent-decoded the target, but neither resolved absolute-form to a path, so the router and the\nmiddleware layer disagreed about which path was being requested.\n\nA second, related defect contributed. Because the adapter always passes `routerOptions` (to install the version\nconstraint), Fastify did not reflect the deprecated **top-level** router options (`ignoreTrailingSlash`,\n`ignoreDuplicateSlashes`, `caseSensitive`, `useSemicolonDelimiter`) in `initialConfig.routerOptions`, which is what\nthe middleware engine reads. Applications passing those options at the top level had middleware normalize paths\ndifferently from the router, which widened the mismatch.\n\n### Proof of concept\n\n```ts\n@Controller('users')\nexport class UsersController {\n @Get()\n findAll() {\n return 'protected data';\n }\n}\n\n@Module({ controllers: [UsersController] })\nexport class AppModule implements NestModule {\n configure(consumer: MiddlewareConsumer) {\n consumer\n .apply((req, res) => res.end('blocked by auth middleware'))\n .forRoutes({ path: 'users', method: RequestMethod.GET });\n }\n}\n```\n\n`supertest` and `light-my-request` always emit origin-form targets, so the request has to be written to the socket:\n\n```js\nconst { connect } = require('node:net');\n\nconst socket = connect(3000, '127.0.0.1', () => {\n socket.write(\n 'GET http://127.0.0.1:3000/users HTTP/1.1\\r\\n' +\n 'Host: 127.0.0.1:3000\\r\\n' +\n 'Connection: close\\r\\n\\r\\n',\n );\n});\nsocket.pipe(process.stdout);\n```\n\nObserved on an affected version: `protected data` — the middleware did not run.\nExpected, and observed on a patched version: `blocked by auth middleware`.\n\n### Patches\n\nFixed in **12.0.2** and **11.2.4**. Upgrading to **12.0.3** or **11.2.5** is recommended.\n\n- The bundled `@fastify/middie` fork was removed and the package now depends on `@fastify/middie@9.3.4`, which\n resolves absolute-form targets before matching.\n- The adapter resolves absolute-form targets in its own route check, mirroring `find-my-way`.\n- Deprecated top-level Fastify router options are folded into `routerOptions` so the middleware engine and the\n router normalize paths identically.\n\n### Workarounds\n\nIf you cannot upgrade, reject non-origin-form request targets before middleware runs. Register the hook on the\nFastify instance **before the application is initialized**, so that it runs ahead of the middleware engine's own\n`onRequest` hook, and confirm with the request above that the rejection takes effect:\n\n```ts\nconst adapter = new FastifyAdapter();\nadapter.getInstance().addHook('onRequest', (request, reply, done) => {\n const target = request.raw.url ?? '';\n // \"*\" is the legitimate request target of \"OPTIONS * HTTP/1.1\"\n if (target[0] !== '/' && target !== '*') {\n reply.code(400).send();\n return;\n }\n done();\n});\n```\n\nRejecting or normalizing absolute-form targets at a reverse proxy in front of the application is equally effective.\n\n### Credit\n\nReported by ZeroVuln Labs.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "@nestjs/platform-fastify"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "11.2.4"
} ]
} ]
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@nestjs/platform-fastify"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "12.0.0"
}, {
"fixed" : "12.0.2"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/fastify/middie/security/advisories/GHSA-hx87-8wv7-pjv8"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/security/advisories/GHSA-9c5c-9qcx-q35q"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/pull/17737"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/commit/5226fe084cf64b357de436f154bc89f2d319b621"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/commit/dda252090ecb65009d9ff366444303796fc44fd7"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/nestjs/nest"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/releases/tag/v11.2.4"
}, {
"type" : "WEB",
"url" : "https://github.com/nestjs/nest/releases/tag/v12.0.2"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-288", "CWE-436" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2026-09-30T14:41:39Z",
"nvd_published_at" : null
}
}