CVE-2026-34237

Published: Mar 31, 2026Modified: Jul 24, 2026

6.1

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Exploitability: 2.8 / Impact: 2.7

Source: security-advisories@github.com (Secondary)

Description

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.

Affected (2)

Products: Lfprojects: Mcp Java Sdk

Lfprojects

1 product

Mcp Java Sdk

Configuration A

2 vulnerable

Vulnerable Software	Affected Versions
Lfprojects Mcp Java Sdk	Before 1.0.1
Lfprojects Mcp Java Sdk	Version 1.1.0

Related CWEs

CWE-942

Permissive Cross-domain Policy with Untrusted Domains

The product uses a cross-domain policy file that includes domains that should not be trusted.

References (3)

https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletSseServerTransportProvider.java#L289

Source: security-advisories@github.com

Patch

https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java#L525

Source: security-advisories@github.com

Patch

https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-hv2w-8mjj-jw22

Source: security-advisories@github.com

MitigationVendor Advisory

Timeline

No history available yet.