8.2
HIGH CVSS 4.0
CVE-2026-5423
Subscription Authentication Bypass via Unverified connectionParams.jwt
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.

INFO

Published Date :

Aug. 6, 2026, 4:16 p.m.

Last Modified :

Aug. 6, 2026, 4:16 p.m.

Remotely Exploit :

Yes !

Source :

3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
Affected Products

The following products are affected by CVE-2026-5423 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
CVSS 4.0 HIGH 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
Solution
Update the @neo4j/graphql library to a patched version to properly verify JWT objects.
  • Update @neo4j/graphql to version 7.5.6 or later.
  • Update @neo4j/graphql to version 5.12.14 or later.
  • Avoid using v6 as it is end-of-life.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-5423.

URL Resource
https://github.com/neo4j/graphql/security/advisories/GHSA-fcpg-3fw5-vc65
https://neo4j.com/security/CVE-2026-5423
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-5423 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-5423 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-5423 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6

    Aug. 06, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://github.com/neo4j/graphql', 'vendor': 'neo4j', 'product': 'graphql', 'versions': [{'status': 'affected', 'version': '7.0.0', 'lessThan': '7.5.6', 'versionType': 'semver'}, {'status': 'affected', 'version': '5.0.0', 'lessThan': '5.12.14', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.0.0', 'versionType': 'semver', 'lessThanOrEqual': '6.6.4'}], 'packageName': '@neo4j/graphql', 'collectionURL': 'https://registry.npmjs.org', 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-302
    Added Reference https://github.com/neo4j/graphql/security/advisories/GHSA-fcpg-3fw5-vc65
    Added Reference https://neo4j.com/security/CVE-2026-5423
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.