CVE-2026-54281

Description

### Impact An authentication bypass vulnerability exists in `@nestjs/platform-fastify` (confirmed on version `11.1.24`, the latest available release at time of report). When middleware is registered through NestJS's `MiddlewareConsumer.forRoutes()` API on the Fastify adapter, an unauthenticated client can bypass the Nest middleware registered for that route by simply appending a trailing slash (`/`) to the request URL. This bypass works on the **default Fastify adapter configuration** — no special router options need to be enabled. Applications using the standard CRUD route shape (`GET /resource` and `GET /resource/:id`) are affected when they protect those routes with `MiddlewareConsumer.forRoutes()` middleware. ### Patches Fixed in `@nestjs/[email protected]` ### References Kudos goes to @a-tt-om

How to fix CVE-2026-54281

To remediate CVE-2026-54281, upgrade the affected package to a fixed version below.

• —upgrade to 11.1.24 or later

Is CVE-2026-54281 being exploited?

No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-54281.

Affected packages (1)

• from 0, < 11.1.24

CVSS scores

References (2)

• PATCHgithub.com/nestjs/nest
• WEBgithub.com/nestjs/nest/security/advisories/GHSA-6v32-fjc9-9qf6