CVE-2026-34237
MCP Java SDK has a Hardcoded Wildcard CORS (Access-Control-Allow-Origin: *)
CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th
MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients. Prior to versions 1.0.1 and 1.1.1, there is a hardcoded wildcard CORS vulnerability. This issue has been patched in versions 1.0.1 and 1.1.1.
| CWE | CWE-942 |
| Vendor | modelcontextprotocol |
| Product | java-sdk |
| Published | Mar 31, 2026 |
| Last Updated | Mar 31, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
modelcontextprotocol / java-sdk
< 1.0.1 < 1.1.1
References
github.com: https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-hv2w-8mjj-jw22 github.com: https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletSseServerTransportProvider.java#L289 github.com: https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java#L525