Interpretation Conflict Affecting @fastify/middie package, versions >=9.1.0 <9.3.3
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published1 Jul 2026
- disclosed1 Jul 2026
- creditJvr2022
Introduced: 1 Jul 2026
NewCVE-2026-14198 (opens in a new tab)How to fix?
Upgrade @fastify/middie to version 9.3.3 or higher.
Overview
@fastify/middie is a Middleware engine for Fastify
Affected versions of this package are vulnerable to Interpretation Conflict via the path parameter handling process. An attacker can gain unauthorized access to protected route handlers by sending a crafted URL containing an encoded slash in the parameter position, causing middleware checks to be bypassed.