CVE-2026-5423
Raw vector
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/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:XSummary
CVE-2026-5423 is a high-severity Authentication Bypass by Assumed-Immutable Data (CWE-302) vulnerability in Neo4J (inferred from references). Its CVSS base score is 8.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 26th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to IA-2 (Identification and Authentication (Organizational Users)) and AC-3 (Access Enforcement) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-54094
Vulnerability Data
@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…
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(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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V7.2.4
Mitigating Controls (NIST 800-53 r5) AI
Mandates proper unique identification and authentication of users, precluding reliance on attacker-controlled immutable assumptions.
Requires server-side enforcement of authorizations instead of trusting client-supplied mutable data for authentication decisions.
Mandates proper identification and authentication for non-organizational users, precluding reliance on attacker-controlled immutable assumptions.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Strong authentication mechanisms directly avoid reliance on attacker-controlled immutable data.
Protecting and verifying identity assertions prevents tampering with data assumed immutable during auth.
Least-privilege authorization policies reduce impact of bypassed authentication but do not address the root flaw.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can discover and block authentication bypasses that rely on mutable data.
Access-control policy can mandate validation of all identity data, reducing reliance on assumed-immutable fields.
Identity-management processes can require verification of mutable attributes, mitigating the root cause.
Proper management of authentication information prevents use of client-controlled tokens or cookies as sole proof of identity.
Access-rights reviews can detect and revoke rights granted via tampered immutable data.
Secure SDLC practices include threat modeling and input-validation requirements that catch assumed-immutable data flaws.