{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-55660",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-17T00:05:03.777Z",
        "datePublished": "2026-07-01T21:00:27.321Z",
        "dateUpdated": "2026-07-02T12:43:47.881Z"
    },
    "containers": {
        "cna": {
            "title": "TinaCMS: Cross-origin postMessage handlers and rich-text URL-sanitization bypass enable stored XSS and session takeover",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-79",
                            "lang": "en",
                            "description": "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-346",
                            "lang": "en",
                            "description": "CWE-346: Origin Validation Error",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-601",
                            "lang": "en",
                            "description": "CWE-601: URL Redirection to Untrusted Site ('Open Redirect')",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-940",
                            "lang": "en",
                            "description": "CWE-940: Improper Verification of Source of a Communication Channel",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 7.6,
                        "baseSeverity": "HIGH",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/tinacms/tinacms/security/advisories/GHSA-g5qx-h5f3-mp2f",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/tinacms/tinacms/security/advisories/GHSA-g5qx-h5f3-mp2f"
                },
                {
                    "name": "https://github.com/tinacms/tinacms/pull/7056",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/tinacms/tinacms/pull/7056"
                }
            ],
            "affected": [
                {
                    "vendor": "tinacms",
                    "product": "tinacms",
                    "versions": [
                        {
                            "version": "< 3.9.3",
                            "status": "affected"
                        }
                    ]
                },
                {
                    "vendor": "tinacms",
                    "product": "@tinacms/app",
                    "versions": [
                        {
                            "version": "< 2.5.6",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-01T21:00:27.321Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Tina is a headless content management system. In versions prior to @tinacms/app 2.5.6 and tinacms 3.9.3, cross-origin postMessage handlers and a rich-text URL-sanitization bypass enable stored XSS and session takeover. The library registers window message listeners — the useTina overlay handler, the OAuth authentication popup handler, and the admin↔preview iframe GraphQL reducer — that act on event.data without verifying event.origin or event.source and post messages using non-specific target origins, while insufficient URL sanitization in rich-text content allows malicious URLs to persist and execute. A page the victim visits (or a window in an opener/iframe relationship with a Tina admin) can forge messages to drive the editor, inject preview content, or observe/forge the OAuth popup channel to take over an authenticated editing session. This issue has been fixed in versions @tinacms/app 2.5.6 and tinacms 3.9.3."
                }
            ],
            "source": {
                "advisory": "GHSA-g5qx-h5f3-mp2f",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-02T12:43:41.136950Z",
                                "id": "CVE-2026-55660",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "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": "2026-07-02T12:43:47.881Z"
                }
            }
        ]
    }
}