CVE-2026-5423: NEO4J Graphql

High severity, CVSS 8.2. EPSS: 0.6% chance of exploitation in the next 30 days.

@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: from 7.0.0, before 7.5.6 (fixed in 7.5.6); from 5.0.0, before 5.12.14 (fixed in 5.12.14); from 6.0.0, up to and including 6.6.4

Published 2026-08-06. Last modified 2026-08-18.