Bypass of Read-Only Mode in MCP Server for Neo4j Databases
CVE-2026-35402

2.3LOW

Key Information:

Vendor

Neo4j-contrib

Status
Mcp-neo4j
Vendor
CVE Published:
17 April 2026

What is CVE-2026-35402?

The mcp-neo4j-cypher product, a server designed to execute Cypher queries on Neo4j databases, has a critical flaw in versions before 0.6.0. This vulnerability allows attackers to circumvent read-only mode enforcement through the use of APOC CALL procedures. Exploiting this issue can lead to unauthorized write operations to the database or even server-side request forgery, posing significant risks to data integrity and system security. The problem has been resolved in version 0.6.0, making it crucial for users to upgrade to this release to safeguard their systems.

Affected Version(s)

mcp-neo4j < 0.6.0

References

https://github.com/neo4j-contrib/mcp-neo4j/security/advis...
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https://github.com/neo4j-contrib/mcp-neo4j/releases/tag/m...
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CVSS V4

Score:
2.3
Severity:
LOW
Confidentiality:
Low
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.