Uncontrolled Recursion Affecting mercurius package, versions <16.8.0
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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Test your applications- Snyk IDSNYK-JS-MERCURIUS-15435881
- published6 Mar 2026
- disclosed6 Mar 2026
- creditLetaoZhao
Introduced: 6 Mar 2026
NewCVE-2026-30241 (opens in a new tab)How to fix?
Upgrade mercurius to version 16.8.0 or higher.
Overview
mercurius is a GraphQL adapter for Fastify
Affected versions of this package are vulnerable to Uncontrolled Recursion in the subscription queries received over WebSocket connections. An attacker can bypass intended query depth restrictions by submitting deeply nested subscription queries via WebSocket, potentially causing excessive resource consumption and service disruption.