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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.0.1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.1.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "product": "java-sdk", "vendor": "modelcontextprotocol"}], "analysis": {"en": {"generated_at": "2026-04-03T17:23:09.439535+00:00", "value": {"mitigation_remediation": ["Upgrade the MCP Java SDK to version\u202f1.0.1 or later (including 1.1.1) where the wildcard CORS header has been removed."], "summary": {"action": "Update SDK", "impact": "Unrestricted cross\u2011origin resource sharing can lead to unintended data exposure from one domain to another."}, "threat_synthesis": {"affected_systems": "The vulnerability affects the Model Context Protocol Java SDK for all releases prior to version 1.0.1 and 1.1.1. Clients and servers that integrate the SDK before these patch releases are susceptible; the patched versions introduce a non\u2011wildcard or configurable CORS policy.", "description_and_impact": "The MCP Java SDK hardcodes the HTTP header Access\u2011Control\u2011Allow\u2011Origin to an asterisk, permitting any web origin to issue cross\u2011origin requests and read responses. This CORS misconfiguration enables potential data leakage or cross\u2011site request forgery if the application exposes sensitive endpoints behind the SDK.", "risk_and_exploitability": "With a CVSS score of 6.1 and an EPSS below 1\u202f%, the risk is moderate and exploitation is unlikely but plausible. Attackers can exploit the flaw remotely by hosting a malicious web page, sending requests to the SDK\u2019s endpoints, and reading the responses due to the permissive CORS header. The vulnerability is not listed in the CISA KEV catalog, indicating no known widespread exploitation currently."}}}}, "created": "2026-03-31T19:54:06.126450+00:00", "updated": "2026-04-03T21:17:34.395481+00:00", "vendors": ["modelcontextprotocol", "modelcontextprotocol$PRODUCT$java-sdk"]}