CVE-2026-34237

medium

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.

References

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

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

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

Details

Source: Mitre, NVD

Published: 2026-03-31

Updated: 2026-06-09

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.1

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