CVE-2026-54281CWE-863

Nest: Middleware Bypass on Fastify via Trailing Slash

High · published June 22, 2026

CVSS v4.0
8.7
EPSS
0%
Percentile
41.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
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
EPSS
0.00498 · 41.9th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-06-22T20:48Z
EPSS history
Timeline
  • 22 JUN 20:48Z
    Nest: Middleware Bypass on Fastify via Trailing Slash
    cvelistv5