{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2025-61672",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2025-09-29T20:25:16.180Z",
        "datePublished": "2025-10-08T14:55:06.378Z",
        "dateUpdated": "2025-10-15T16:11:07.284Z"
    },
    "containers": {
        "cna": {
            "title": "Synapse: Invalid device keys degrade federation functionality",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-1287",
                            "lang": "en",
                            "description": "CWE-1287: Improper Validation of Specified Type of Input",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "LOW",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "LOW",
                        "vulnAvailabilityImpact": "LOW",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 5.3,
                        "baseSeverity": "MEDIUM",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/element-hq/synapse/security/advisories/GHSA-fh66-fcv5-jjfr",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/element-hq/synapse/security/advisories/GHSA-fh66-fcv5-jjfr"
                },
                {
                    "name": "https://github.com/element-hq/synapse/pull/17097",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/element-hq/synapse/pull/17097"
                },
                {
                    "name": "https://github.com/element-hq/synapse/commit/26aaaf9e48fff80cf67a20c691c75d670034b3c1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/element-hq/synapse/commit/26aaaf9e48fff80cf67a20c691c75d670034b3c1"
                },
                {
                    "name": "https://github.com/element-hq/synapse/commit/7069636c2d6d1ef2022287addf3ed8b919ef2740",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/element-hq/synapse/commit/7069636c2d6d1ef2022287addf3ed8b919ef2740"
                },
                {
                    "name": "https://github.com/element-hq/synapse/releases/tag/v1.138.3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/element-hq/synapse/releases/tag/v1.138.3"
                },
                {
                    "name": "https://github.com/element-hq/synapse/releases/tag/v1.139.1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/element-hq/synapse/releases/tag/v1.139.1"
                }
            ],
            "affected": [
                {
                    "vendor": "element-hq",
                    "product": "synapse",
                    "versions": [
                        {
                            "version": "< 1.138.3",
                            "status": "affected"
                        },
                        {
                            "version": "= 1.139.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2025-10-08T14:55:06.378Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Synapse is an open source Matrix homeserver implementation. Lack of validation for device keys in Synapse before 1.138.3 and in Synapse 1.139.0 allow an attacker registered on the victim homeserver to degrade federation functionality, unpredictably breaking outbound federation to other homeservers. The issue is patched in Synapse 1.138.3, 1.138.4, 1.139.1, and 1.139.2. Note that even though 1.138.3 and 1.139.1 fix the vulnerability, they inadvertently introduced an unrelated regression. For this reason, the maintainers of Synapse recommend skipping these releases and upgrading straight to 1.138.4 and 1.139.2."
                }
            ],
            "source": {
                "advisory": "GHSA-fh66-fcv5-jjfr",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2025-10-15T16:10:58.297046Z",
                                "id": "CVE-2025-61672",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-10-15T16:11:07.284Z"
                }
            }
        ]
    }
}