{"cve":"CVE-2026-34237","nvd":{"published":"2026-03-31T16:16:32.923","modified":"2026-07-24T20:10:00.147","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-942"],"references":["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","https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-hv2w-8mjj-jw22"],"products":["lfprojects:mcp_java_sdk"],"source":"nvd","synced_at":"2026-10-19T22:28:18.033120106+00:00"},"epss":{"cve":"CVE-2026-34237","score":0.00231,"percentile":0.14005,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-hv2w-8mjj-jw22","url":"https://osv.dev/vulnerability/GHSA-hv2w-8mjj-jw22","summary":"MCP Java SDK has a Hardcoded Wildcard CORS (Access-Control-Allow-Origin: *)","modified":"2026-09-10T03:50:39.742363136Z","packages":[{"ecosystem":"Maven","name":"io.modelcontextprotocol.sdk:mcp-core","purl":"pkg:maven/io.modelcontextprotocol.sdk/mcp-core","ranges":[">=1.0.0 <1.0.1"],"fixed":["1.0.1"]},{"ecosystem":"Maven","name":"io.modelcontextprotocol.sdk:mcp-core","purl":"pkg:maven/io.modelcontextprotocol.sdk/mcp-core","ranges":[">=1.1.0 <1.1.1"],"fixed":["1.1.1"]},{"ecosystem":"Maven","name":"io.modelcontextprotocol.sdk:mcp-core","purl":"pkg:maven/io.modelcontextprotocol.sdk/mcp-core","ranges":["<0.18.3"],"fixed":["0.18.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}