{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-42559",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-04-28T16:56:50.192Z",
        "datePublished": "2026-05-14T14:24:56.090Z",
        "dateUpdated": "2026-05-14T16:00:33.149Z"
    },
    "containers": {
        "cna": {
            "title": "RMCP: DNS rebinding vulnerability in rmcp Streamable HTTP server transport",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-346",
                            "lang": "en",
                            "description": "CWE-346: Origin Validation Error",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-350",
                            "lang": "en",
                            "description": "CWE-350: Reliance on Reverse DNS Resolution for a Security-Critical Action",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 8.8,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "REQUIRED",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/modelcontextprotocol/rust-sdk/security/advisories/GHSA-89vp-x53w-74fx",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/modelcontextprotocol/rust-sdk/security/advisories/GHSA-89vp-x53w-74fx"
                },
                {
                    "name": "https://github.com/modelcontextprotocol/rust-sdk/issues/815",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/modelcontextprotocol/rust-sdk/issues/815"
                },
                {
                    "name": "https://github.com/modelcontextprotocol/rust-sdk/issues/822",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/modelcontextprotocol/rust-sdk/issues/822"
                },
                {
                    "name": "https://github.com/modelcontextprotocol/rust-sdk/pull/764",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/modelcontextprotocol/rust-sdk/pull/764"
                },
                {
                    "name": "https://github.com/modelcontextprotocol/rust-sdk/commit/8e22aa2de28df5a285eed87c11cd89bf15fa90d3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/modelcontextprotocol/rust-sdk/commit/8e22aa2de28df5a285eed87c11cd89bf15fa90d3"
                }
            ],
            "affected": [
                {
                    "vendor": "modelcontextprotocol",
                    "product": "rust-sdk",
                    "versions": [
                        {
                            "version": "< 1.4.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-05-14T14:24:56.090Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "RMCP is an official Rust SDK for the Model Context Protocol. Prior to version 1.4.0, the rmcp crate's Streamable HTTP server transport (crates/rmcp/src/transport/streamable_http_server/) did not validate the incoming Host header. This allowed a malicious public website, via a DNS rebinding attack, to send authenticated requests to an MCP server running on the victim's loopback or private-network interface. This vulnerability is fixed in 1.4.0."
                }
            ],
            "source": {
                "advisory": "GHSA-89vp-x53w-74fx",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-05-14T16:00:22.834947Z",
                                "id": "CVE-2026-42559",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "dateUpdated": "2026-05-14T16:00:33.149Z"
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}