CVE-2026-34237
1 advisory.
Maven/io.modelcontextprotocol.sdk:mcp-core CVE-2026-34237: medium 6.1
MCP Java SDK has a Hardcoded Wildcard CORS (Access-Control-Allow-Origin: *)
Action: Upgrade io.modelcontextprotocol.sdk:mcp-core to 0.18.3 (0.18.x), 1.0.1 (1.0.x) or 1.1.1 (1.1.x) or later.
Affected
| introduced | fixed | last affected |
|---|---|---|
| 1.0.0 | 1.0.1 | - |
| 1.1.0 | 1.1.1 | - |
| 0 | 0.18.3 | - |
Fixed versions
| 1.0.1 | 1.1.1 | 0.18.3 |
Sources
- osv: GHSA-hv2w-8mjj-jw22
- https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-hv2w-8mjj-jw22
- https://nvd.nist.gov/vuln/detail/CVE-2026-34237
- https://cheatsheetseries.owasp.org/cheatsheets/HTTP_Headers_Cheat_Sheet.html#access-control-allow-origin
- https://github.com/modelcontextprotocol/java-sdk
- https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletSseServerTransportProvider.java#L289
- https://github.com/modelcontextprotocol/java-sdk/blob/main/mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java#L525
CVE-2026-34237 · published · modified · JSON