CVE-2026-33804

CVE-2026-33804 affects @fastify/middie v9.3.1 and earlier, where middleware bypass can occur when the deprecated top-level ignoreDuplicateSlashes option is enabled. The middleware’s path-matching does not account for duplicate-slash normalization performed by Fastify’s router, allowing requests w...

CVE-2026-33804 @fastify/middie vulnerable to middleware bypass via deprecated ignoreDuplicateSlashes option

@fastify/middie versions 9.3.1 and earlier are vulnerable to middleware bypass when the deprecated Fastify ignoreDuplicateSlashes option is enabled. The middleware path matching logic does not account for duplicate slash normalization performed by Fastify's router, allowing requests with duplicat...

CVE-2026-33804 @fastify/middie vulnerable to middleware bypass via deprecated ignoreDuplicateSlashes option

@fastify/middie versions 9.3.1 and earlier are vulnerable to middleware bypass when the deprecated Fastify ignoreDuplicateSlashes option is enabled. The middleware path matching logic does not account for duplicate slash normalization performed by Fastify's router, allowing requests with duplicat...

CVE-2026-33804 @fastify/middie vulnerable to middleware bypass via deprecated ignoreDuplicateSlashes option

@fastify/middie versions 9.3.1 and earlier are vulnerable to middleware bypass when the deprecated Fastify ignoreDuplicateSlashes option is enabled. The middleware path matching logic does not account for duplicate slash normalization performed by Fastify's router, allowing requests with duplicat...

CVE-2026-6270 @fastify/middie vulnerable to middleware authentication bypass in child plugin scopes

@fastify/middie versions 9.3.1 and earlier do not register inherited middleware directly on child plugin engine instances. When a Fastify application registers authentication middleware in a parent scope and then registers child plugins with @fastify/middie, the child scope does not inherit the...

CVE-2026-6414

@fastify/static versions 8.0.0 through 9.1.0 decode percent-encoded path separators %2F before filesystem resolution, while Fastify's router treats them as literal characters. This mismatch allows attackers to bypass route-based middleware or guards that protect files served by @fastify/static. F...

Improper Access Control

@fastify/express is vulnerable to Improper Access Control. The vulnerability is due to incorrect path handling in the onRegister function, where middleware paths are duplicated when inherited by child plugins, causing them to not match incoming requests and resulting in bypass of security control...

GHSA-HRWM-HGMJ-7P9C @fastify/express's middleware path doubling causes authentication bypass in child plugin scopes

Summary @fastify/express v4.0.4 contains a path handling bug in the onRegister function that causes middleware paths to be doubled when inherited by child plugins. This results in complete bypass of Express middleware security controls for all routes defined within child plugin scopes that share ...

@fastify/express's middleware path doubling causes authentication bypass in child plugin scopes

Summary @fastify/express v4.0.4 contains a path handling bug in the onRegister function that causes middleware paths to be doubled when inherited by child plugins. This results in complete bypass of Express middleware security controls for all routes defined within child plugin scopes that share ...

EUVD-2026-22880

@fastify/express's middleware path doubling causes authentication bypass in child plugin scopes...

CVE-2026-33804: Interpretation Conflict

@fastify/middie versions 9.3.1 and earlier are vulnerable to middleware bypass when the deprecated Fastify ignoreDuplicateSlashes option is enabled. The middleware path matching logic does not account for duplicate slash normalization performed by Fastify's router, allowing requests with duplicat...

CVE-2026-6270: Interpretation Conflict

@fastify/middie versions 9.3.1 and earlier do not register inherited middleware directly on child plugin engine instances. When a Fastify application registers authentication middleware in a parent scope and then registers child plugins with @fastify/middie, the child scope does not inherit the...

PT-2026-35071

Name of the Vulnerable Software and Affected Versions Budibase versions prior to 3.35.4 Description The authenticated middleware uses unanchored regular expressions to match public endpoint patterns against the ctx.request.url variable. Because ctx.request.url in Koa includes the query string, an...

CVE-2026-6414: Improper Handling of URL Encoding (Hex Encoding)

@fastify/static versions 8.0.0 through 9.1.0 decode percent-encoded path separators %2F before filesystem resolution, while Fastify's router treats them as literal characters. This mismatch allows attackers to bypass route-based middleware or guards that protect files served by @fastify/static. F...

PT-2026-33320

Name of the Vulnerable Software and Affected Versions @fastify/middie versions prior to 9.3.2 Description Inherited middleware is not registered directly on child plugin engine instances. When authentication middleware is registered in a parent scope and child plugins are registered with...

PT-2026-33323

Name of the Vulnerable Software and Affected Versions @fastify/middie versions prior to 9.3.2 Description A middleware bypass exists when the deprecated ignoreDuplicateSlashes option is enabled. The middleware path matching logic fails to account for duplicate slash normalization performed by the...

PT-2026-35301

Summary The authenticated middleware uses unanchored regular expressions to match public no-auth endpoint patterns against ctx.request.url. Since ctx.request.url in Koa includes the query string, an attacker can access any protected endpoint by appending a public endpoint path as a query paramete...

PT-2026-35323

Summary createRouteMatcher in @clerk/nextjs, @clerk/nuxt, and @clerk/astro can be bypassed by certain crafted requests, allowing them to skip middleware gating and reach downstream handlers. Sessions are not compromised and no existing user can be impersonated - the bypass only affects the...

PT-2026-35082

Name of the Vulnerable Software and Affected Versions @clerk/astro versions prior to 1.5.7 @clerk/astro versions prior to 2.17.10 @clerk/astro versions prior to 3.0.15 @clerk/nextjs versions prior to 5.7.6 @clerk/nextjs versions prior to 6.39.2 @clerk/nextjs versions prior to 7.2.1 @clerk/nuxt...

@fastify/middie security vulnerabilities

@fastify/middie is an open-source middleware engine developed by Fastify. Versions of @fastify/middie prior to 9.3.1 contained security vulnerabilities. These vulnerabilities stemmed from the lack of registration of inherited middleware on sub-plugin engine instances, which could lead to bypassin...