CVE-2026-34237

MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients. Prior to versions 0.83.0, 1.0.1, and 1.1.1, there is a hardcoded wildcard CORS vulnerability. This issue has been patched in versions 0.83.0, 1.0.1, and 1.1.1.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletSseServerTransportProvider.java#L289	Patch
https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java#L525	Patch
https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-hv2w-8mjj-jw22	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:lfprojects:mcp_java_sdk::::::::
	cpe:2.3:a:lfprojects:mcp_java_sdk:1.1.0:::::::*

History

No history.

Information

Published : 2026-03-31 16:16

Updated : 2026-07-24 20:10

NVD link : CVE-2026-34237

Mitre link : CVE-2026-34237

CVE.ORG link : CVE-2026-34237

JSON object : View

Products Affected

lfprojects

mcp_java_sdk

CWE

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

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