Vulnerability in Lfprojects Mcp Java Sdk
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.
EPSS: 0.002 (13.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Lfprojects Mcp_java_sdk — versions 1.1.0
- Modelcontextprotocol Java-sdk — versions < 1.1.1, >= 1.1.0, < 1.1.1, < 0.18.3
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-34237?
- CVE-2026-34237 is a medium-severity vulnerability in Lfprojects Mcp Java Sdk, classified under Permissive Cross-domain Policy with Untrusted Domains. CVSS score: 6.1/10. Published 2026-03-31.
- How severe is CVE-2026-34237?
- Medium severity. CVSS v3 base score is 6.1 out of 10.