{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-18918",
        "assignerOrgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c",
        "state": "PUBLISHED",
        "assignerShortName": "eclipse",
        "dateReserved": "2026-08-05T07:44:04.388Z",
        "datePublished": "2026-08-28T08:54:07.990Z",
        "dateUpdated": "2026-08-31T12:27:40.249Z"
    },
    "containers": {
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                "orgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c",
                "shortName": "eclipse",
                "dateUpdated": "2026-08-31T12:27:40.249Z"
            },
            "title": "OAuth 1.0 session-fixation chain via unauthenticated provisional-consumer registration and insecure v1_0Allowed default",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-863",
                            "description": "CWE-863",
                            "type": "CWE"
                        }
                    ]
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            ],
            "impacts": [
                {
                    "capecId": "CAPEC-114",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-114"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Eclipse Foundation",
                    "product": "Eclipse Lyo",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "2.0.0",
                            "lessThan": "7.0.0",
                            "versionType": "custom"
                        }
                    ],
                    "defaultStatus": "unaffected"
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            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In Eclipse Lyo versions 2.0.0 to 7.0.0, OAuth server authorization checks can be bypassed when the 2-legged auth is supported by the server. In those cases, application that based their authz filters upon Lyo-provided `AbstractAdapterCredentialsFilter`, are vulnerable. An attacked can create a provisional trusted client (valid use-case) but then it can be used as a trusted client immediately without requiring the administrator approval to clear the provisional status. The 3-legged path requiring user interaction is not vulnerable and rejects provisional clients.",
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                            "value": "<p>In Eclipse Lyo versions 2.0.0 to 7.0.0, OAuth server authorization checks can be bypassed when the 2-legged auth is supported by the server. In those cases, application that based their authz filters upon Lyo-provided `AbstractAdapterCredentialsFilter`, are vulnerable. An attacked can create a provisional trusted client (valid use-case) but then it can be used as a trusted client immediately without requiring the administrator approval to clear the provisional status. The 3-legged path requiring user interaction is not vulnerable and rejects provisional clients.</p>"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/eclipse-lyo/lyo/releases/tag/v6.0.1.Final"
                },
                {
                    "url": "https://github.com/eclipse-lyo/lyo/releases/tag/v7.0.0.Beta3"
                },
                {
                    "url": "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/221"
                }
            ],
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                            "lang": "en",
                            "value": "GENERAL"
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                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "YES",
                        "Recovery": "USER",
                        "valueDensity": "CONCENTRATED",
                        "vulnerabilityResponseEffort": "LOW",
                        "providerUrgency": "RED",
                        "version": "4.0",
                        "baseSeverity": "CRITICAL",
                        "baseScore": 9.1,
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/AU:Y/R:U/V:C/RE:L/U:Red"
                    }
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Eclipse Foundation Security Team",
                    "type": "finder"
                }
            ],
            "source": {
                "discovery": "INTERNAL"
            },
            "x_generator": {
                "engine": "Vulnogram 1.0.5"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-28T15:03:52.629478Z",
                                "id": "CVE-2026-18918",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-08-28T15:04:16.704Z"
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}