Signal is active with 2 mentions in latest observed window
Recommended action window: Monitor and triage in normal cycle
NVD description
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 deny all input, fastify treats it as a missing schema, compiles no validator, and runs the route handler on any request. An unauthenticated remote client can therefore reach a handler that a valid deny-all schema was intended to make unreachable, a complete validation bypass that can lead to unauthorized state changes or execution of disabled operations. Users should upgrade to fastify 5.12.2 or later.
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
AVAILABLE
Momentum
NONE
If you run products in this scope, you should treat this CVE as relevant to your environment.
CVE-2026-84469 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… https://www.cve.org/CVERecord?id=CVE-2026-84469
Post summary
Fastify versions earlier than 5.12.2 mistakenly compile request schemas using JavaScript truthiness, treating JSON Schema Draft 7’s boolean false as valid, exposing a potential vulnerability.
🚨 High-severity security fix in fastify@5.12.2 just released! Patches CVE-2026-84469: request validation bypass via skipped boolean false schemas. https://github.com/fastify/fastify/security/advisories/GHSA-hwr6-493r-vm6h
Post summary
Fastify released a high‑severity patch for CVE‑2026‑84469, fixing a request validation bypass vulnerability and providing technical details in the advisory.
1 of 1 entries
| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | fastify | fastify | - | node.js | - |