CVE-2026-54281
Nest: Middleware Bypass on Fastify via Trailing Slash
Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.24, an authentication bypass vulnerability exists in @nestjs/platform-fastify. 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. This vulnerability is fixed in 11.1.24.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
8.7
Nest: Middleware Bypass on Fastify via Trailing Slash
Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.24, an authentication bypass vulnerability exists in @nestjs/platform-fastify. 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. This vulnerability is fixed in 11.1.24.
- Record
CVE-2026-54281- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-38398
8.7
Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.24, an authentication bypass vulnerability exists in @nestjs/platform-fastify. 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. This vulnerability is fixed in 11.1.24.
- Record
EUVD-2026-38398- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6v32-fjc9-9qf6
8.7
Nest: Middleware Bypass on Fastify via Trailing Slash
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
- Record
GHSA-6v32-fjc9-9qf6- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
NVD
8.7
Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.24, an authentication bypass vulnerability exists in @nestjs/platform-fastify. 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. This vulnerability is fixed in 11.1.24.
- Record
CVE-2026-54281- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
8.7
Nest: Middleware Bypass on Fastify via Trailing Slash
Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.24, an authentication bypass vulnerability exists in @nestjs/platform-fastify. 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. This vulnerability is fixed in 11.1.24.
- Record
CVE-2026-54281- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVGHSA-6v32-fjc9-9qf6
8.7
Nest: Middleware Bypass on Fastify via Trailing Slash
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
- Record
GHSA-6v32-fjc9-9qf6- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@nestjs/platform-fastifynpm |
through 11.1.23 | 11.1.24 |
@nestjs/platform-fastifynpm |
before 11.1.24 | 11.1.24 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-54281 is a high vulnerability (CVSS 8.7) in Nestjs Nest, published June 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.50%, the 42nd percentile. Fixed in @nestjs/platform-fastify 11.1.24.