DNS Rebinding Vulnerability in MCP Java SDK by Model Context Protocol
CVE-2026-35568

7.6HIGH

Key Information:

Vendor

Modelcontextprotocol

Status
Java-sdk
Vendor
CVE Published:
7 April 2026

What is CVE-2026-35568?

The MCP Java SDK, designed for Model Context Protocol servers and clients, is vulnerable to a DNS rebinding attack prior to version 1.0.0. This vulnerability permits attackers to gain unauthorized access to a locally or network-private MCP server through a victim's browser. By exploiting this weakness, an attacker can execute server tool calls as if they were a legitimate, locally running AI agent connected to the MCP. A fix is available in version 1.0.0, which addresses this critical issue.

Affected Version(s)

java-sdk < 1.0.0

References

https://github.com/modelcontextprotocol/java-sdk/security...
x_refsource_CONFIRM
https://github.com/modelcontextprotocol/java-sdk/releases...
x_refsource_MISC

CVSS V4

Score:
7.6
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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