# CVE-2026-5423

## Summary

- **CVE ID:** CVE-2026-5423
- **Severity:** HIGH
- **CVSS Score:** 8.2 (CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N)
- **CWE:** CWE-302
- **Published:** Aug 6, 2026
- **Last Modified:** Aug 6, 2026

## Description

@neo4j/graphql library versions prior to 7.5.6 fail to verify the authenticity of a client-supplied, pre-decoded JWT object passed through GraphQL subscription connectionParams. As a result, any unauthenticated remote client that can open a GraphQL-over-WebSocket connection can forge arbitrary JWT claims (e.g. sub, roles) in connectionParams.jwt and have them accepted as authenticated identity for the purposes of @authentication and @subscriptionsAuthorization directive evaluation. This allows a fully unauthenticated attacker to receive subscription events that should be restricted to specific authenticated roles/users.
Upgrade the library to versions 7.5.6+ or 5.12.14+. v6 is end-of-life and will not receive a fix.

## Affected Products

- neo4j — graphql (7.0.0)
- neo4j — graphql (5.0.0)
- neo4j — graphql (6.0.0)

## References

- [CNA](https://neo4j.com/security/CVE-2026-5423)
- [CNA](https://github.com/neo4j/graphql/security/advisories/GHSA-fcpg-3fw5-vc65)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.36%
- **EPSS Percentile:** 28.9

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._