WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks_CVE-2026-40911

{
    "lastseen": "",
    "description": "WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix.",
    "published": "2026-04-21T19:55:37.195Z",
    "modified": "2026-04-21T19:55:37.195Z",
    "type": "cve",
    "title": "WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks",
    "source": "GitHub_M",
    "references": "https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr\nhttps://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd",
    "id": "CVE-2026-40911",
    "bulletinFamily": "",
    "cwe": [
        "CWE-94"
    ],
    "cvelist": null,
    "sourceData": "WWBN AVideo <= 29.0",
    "sourceHref": "",
    "cvss": {
        "score": 10,
        "severity": "CRITICAL",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
        "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": "AVideo",
    "version": "<= 29.0",
    "vendor": "WWBN",
    "ai_description": "Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks",
    "ai_severity": "Critical",
    "ai_vendor": "WWBN",
    "ai_product": "AVideo",
    "ai_version": "<= 29.0",
    "ai_score": 10
}