CVE-2026-84469

fastify versions before 5.12.2 use JavaScript truthiness to decide whether to compile a request schema. Because JSON Schema Draft 7 defines the boolean false as a valid schema that rejects every instance, an application that assigns false to a route's body, querystring, params, or headers schema ...

CVE-2026-84469 fastify vulnerable to request validation bypass via skipped boolean false schemas

fastify versions before 5.12.2 decide whether to compile a request schema based on JavaScript truthiness, but JSON Schema Draft 7 defines the boolean false as a valid schema that rejects every instance. When an application assigns false to a route's body, querystring, params, or headers schema to...

Improper Validation of Specified Type of Input

Overview fastify is an overhead web framework, for Node.js. Affected versions of this package are vulnerable to Improper Validation of Specified Type of Input via the route schema handling in lib/route.js, lib/schemas.js, and lib/validation.js. An attacker can reach a route handler with arbitrary...

CVE-2026-84469 fastify vulnerable to request validation bypass via skipped boolean false schemas

fastify versions before 5.12.2 decide whether to compile a request schema based on JavaScript truthiness, but JSON Schema Draft 7 defines the boolean false as a valid schema that rejects every instance. When an application assigns false to a route's body, querystring, params, or headers schema to...

CVE-2026-84504

A flaw was found in fastify. An authenticated low-privilege caller can exploit a vulnerability where the framework incorrectly processes the result of an Ajv asynchronous async validator. If a request body contains a root-level property named 'value', fastify replaces the entire request body with...

CVE-2026-76169 fastify vulnerable to authentication bypass via malformed URLs reaching encapsulated not-found handlers

fastify versions = 4.0.0 and before 5.12.2 can route a malformed URL sent under one plugin prefix to the custom not-found handler of a different sibling plugin, and invoke it without the preHandler hook declared for that handler. The internal not-found router for encapsulated handlers dispatches...

CVE-2026-76169

Fastify (versions >= 4.0.0 and

CVE-2026-76169 fastify vulnerable to authentication bypass via malformed URLs reaching encapsulated not-found handlers

fastify versions = 4.0.0 and before 5.12.2 can route a malformed URL sent under one plugin prefix to the custom not-found handler of a different sibling plugin, and invoke it without the preHandler hook declared for that handler. The internal not-found router for encapsulated handlers dispatches...

CVE-2026-76169 fastify vulnerable to authentication bypass via malformed URLs reaching encapsulated not-found handlers

fastify versions = 4.0.0 and before 5.12.2 can route a malformed URL sent under one plugin prefix to the custom not-found handler of a different sibling plugin, and invoke it without the preHandler hook declared for that handler. The internal not-found router for encapsulated handlers dispatches...

CVE-2026-84504

fastify versions before 5.12.2 are vulnerable to a request body replacement flaw caused by an Ajv async validator result collision. When a request that passes its route schema contains a root-level property named value, fastify treats that property as the value result protocol used by custom vali...

CVE-2026-84504 fastify vulnerable to request body replacement via an async validation result collision

fastify versions before 5.12.2 treat the object resolved by a successful Ajv async validator as the value result protocol used by custom validator compilers. If a request that passes its route schema contains a property named value at the root, fastify replaces the entire request body with that...

CVE-2026-84504 fastify vulnerable to request body replacement via an async validation result collision

fastify versions before 5.12.2 treat the object resolved by a successful Ajv async validator as the value result protocol used by custom validator compilers. If a request that passes its route schema contains a property named value at the root, fastify replaces the entire request body with that...

Incorrect Behavior Order: Early Validation

Overview fastify is an overhead web framework, for Node.js. Affected versions of this package are vulnerable to Incorrect Behavior Order: Early Validation through the request validation path in lib/validation.js. An attacker can replace the validated request body, or trigger a validation failure,...

@agent-tool-platform/ast-summarizer (>=0.1.0, <=0.1.1), @agent-tool-platform/runtime (>=0.1.0, <=0.1.2) +582 more potentially affected by CVE-2026-84504 via fastify (>=5.0.0, <=5.12.1)

fastify NPM version =5.0.0, =0.1.0, =0.1.0, =0.1.0, =1.0.4, =0.0.0-vBETA-20260417080530, =0.0.1, =1.60.2, =1.0.0, =0.0.0, =2.0.1, =0.1.0, =0.1.0, =0.2.2 and more Source cves: CVE-2026-84504 Source advisory: SNYK:JS-FASTIFY-19639040...

CVE-2026-84504 fastify vulnerable to request body replacement via an async validation result collision

fastify versions before 5.12.2 treat the object resolved by a successful Ajv async validator as the value result protocol used by custom validator compilers. If a request that passes its route schema contains a property named value at the root, fastify replaces the entire request body with that...

CVE-2026-85184 @fastify/middie vulnerable to path-scoped middleware bypass via absolute-form request target

@fastify/middie versions = 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request...

CVE-2026-85184 @fastify/middie vulnerable to path-scoped middleware bypass via absolute-form request target

@fastify/middie versions = 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request...

CVE-2026-85184

@fastify/middie (a Fastify plugin for HTTP middleware) versions 9.1.0 through 9.3.3 are affected by a path-scoped middleware bypass. The root cause is a mismatch: middie evaluates the raw request target to decide whether to run path-scoped middleware, while the Fastify router resolves an absolute...

CVE-2026-85184 @fastify/middie vulnerable to path-scoped middleware bypass via absolute-form request target

@fastify/middie versions = 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request...

EUVD-2026-70979

@fastify/middie versions = 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request...