Uncaught Exception in mercurius
Priority LOW 36CWE-754Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.
Summary
Mercurius is a GraphQL adapter for Fastify. Any users from [email protected] to 8.11.1 are subjected to a denial of service attack by sending a malformed JSON to `/graphql` unless they are using a custom error handler. The vulnerability has been fixed in https://github.com/mercurius-js/mercurius/pull/678 and shipped as v8.11.2. As a workaround users may use a custom error handler.
Why it matters now
EPSS 0.01572 75th percentileScored 2026-11-07
Fix Fixed mercurius (mercurius-js): 8.11.2mercurius (npm): 8.11.2
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| mercurius-js | mercurius | 8.10.0 to before 8.11.2 | 8.11.2 | Patch available | CNA |
| — | mercurius (npm) | 8.10.0 to before 8.11.2 | 8.11.2 | Patch available | GHSA-273r-rm8g-7f3x |
- mercurius Vendormercurius-js Affected 8.10.0 to before 8.11.2 Fixed in 8.11.2 Patch available CNA
- mercurius (npm) Vendor— Affected 8.10.0 to before 8.11.2 Fixed in 8.11.2 Patch available GHSA-273r-rm8g-7f3x
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mercurius_project:mercurius:*:*:*:*:*:node.js:*:* | 8.10.0 to before 8.11.2 | Vulnerable | mercurius-js |
- cpe:2.3:a:mercurius_project:mercurius:*:*:*:*:*:node.js:*:* Versions 8.10.0 to before 8.11.2 Vulnerable ·mercurius-js
Remediation
- Fix · CNA mercurius (mercurius-js) Fixed in 8.11.2
- Fix · GHSA-273r-rm8g-7f3x mercurius (npm) Fixed in 8.11.2 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2021-43801
- 2026-10-03 Alias added: GHSA-273r-rm8g-7f3x
References
Patch 3
More mercurius-js Mercurius vulnerabilities
- TI-2023-08726 Mercurius is vulnerable to denial of service (DoS) when using subscriptions CVSS 3.1HIGH 7.5
- TI-2025-39610 Mercurius: Incorrect Content-Type parsing can lead to CSRF attack CVSS 3.1MEDIUM 5.4
- TI-2026-23474 Mercurius: queryDepth limit bypassed for WebSocket subscriptions CVSS 4.0LOW 2.7
Sources
- CVE-2021-43801 · CVE Program
- CVE-2021-43801 · NVD
- FIRST EPSS
- GHSA-273r-rm8g-7f3x · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences