Relay Server WebSocket authentication bypass when token is omitted_CVE-2026-42889

{
    "lastseen": "",
    "description": "Relay adds real-time collaboration to Obsidian. Relay Server versions 0.9.0 through 0.9.6 contain an authentication bypass in the multi-document WebSocket endpoints. When authentication is configured, WebSocket connections without a token query parameter were incorrectly treated as having full server permissions. An unauthenticated network attacker who knows or guesses a document ID could connect to the document sync WebSocket and read or modify document contents without a valid document token. This vulnerability is fixed in 0.9.7.",
    "published": "2026-05-12T19:30:05.552Z",
    "modified": "2026-05-12T19:30:05.552Z",
    "type": "cve",
    "title": "Relay Server WebSocket authentication bypass when token is omitted",
    "source": "GitHub_M",
    "references": "https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm",
    "id": "CVE-2026-42889",
    "bulletinFamily": "",
    "cwe": [
        "CWE-863",
        "CWE-639"
    ],
    "cvelist": null,
    "sourceData": "No-Instructions relay-server >= 0.9.0, < 0.9.7",
    "sourceHref": "",
    "cvss": {
        "score": 9.1,
        "severity": "CRITICAL",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "relay-server",
    "version": ">= 0.9.0, < 0.9.7",
    "vendor": "No-Instructions",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}