EUVD-2026-70989

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-2026-84469

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...