Telenia Software TVox <= 26.5.3 (set_env.php) Authentication Bypass Vulnerability

• Software Link:

https://www.teleniasoftware.com

• Affected Versions:

Version 26.5.3 and prior 26.x versions.

Version 24.9.21 and prior 24.x versions.

Older versions may be affected as well.

• Vulnerability Description:

The vulnerable code is located within the /opt/telenia/tvox/php/siti/t-vox/manager/set_env.php script.

Specifically, into the redirectToLoginAdminIRequestHaveAccessToken() function:

293function redirectToLoginAdminIRequestHaveAccessToken($force = false) {
294    $current_page = str_replace("/", "", strrchr($_SERVER['PHP_SELF'], "/"));
295    if ($current_page != "login_admin.php") {
296        $request_uri = $_SERVER["REQUEST_URI"];
297        $accessToken = @trim($force ? $_REQUEST["access_token"] : $_GET["access_token"]);
298        
299        if ($accessToken !== "" && (!isset($_SESSION["wso2auth"]) || ( isset($_SESSION["wso2auth"]) && $_SESSION["wso2auth"]->accessToken !== trim($accessToken)) )) {
300            $force = true;
301            if (@trim($_GET["access_token"]) != "") {
302                $parsedUrl = parse_url($request_uri);
303                $parsedUrl["query"] = query_string_exclude(array('access_token'), $_GET);
304                if ($parsedUrl["query"] != "") {
305                    $request_uri = $parsedUrl["path"] . "?" . $parsedUrl["query"];
306                }
307            }
308        }
309
310        if ($force) {
311            $_SESSION["request_uri"] = $request_uri;
312            unset($_REQUEST["access_token"]);
313            $_SESSION['requestSave'] = $_REQUEST;
314            header("Location: /tvox/manager/html/login_admin.php" . ( $accessToken === "" ? "" : "?access_token=" . $accessToken ));
315            exit;
316        }
317    }
318}

This function is invoked to verify whether the user is already authenticated. If the user is not authenticated, execution reaches line 314, where the user is redirected to the login page, and it terminates at line 315 via an exit statement.

The issue is that this authentication check is only enforced when the value of the $current_page variable differs from login_admin.php (line 295). Since $current_page is populated using the value of $_SERVER['PHP_SELF'] (at line 294), an attacker can bypass the authentication check by simply appending the string /login_admin.php to the path of the target PHP script. As a result, the application incorrectly treats the request as if it were targeting the login page, allowing unauthenticated access to all PHP scripts exposed under the /tvox/manager/html/ path.

• Proof of Concept:

https://karmainsecurity.com/pocs/tvox_root_rce.php

• Solution:

No official solution is currently available.

• Disclosure Timeline:

[22/05/2026] – Vendor was contacted, no response

[26/05/2026] – Vendor was notified about this vulnerability, no response

[27/05/2026] – Vendor was notified about 60-day disclosure deadline policy, no response

[26/06/2026] – Vendor was contacted again along with CSIRT Italy, no response from CSIRT

[08/07/2026] – First vendor response, asking for vulnerability details

[09/07/2026] – Vulnerability details safely provided to the vendor

[20/07/2026] – Vendor was contacted again, asking for an update

[21/07/2026] – Vendor replied a security patch will be released by the end of July

[21/07/2026] – CVE identifier requested

[21/07/2026] – CVE identifier assigned

[27/07/2026] – Reached 60-day disclosure deadline, still no official solution

[03/08/2026] – Public disclosure

• CVE Reference:

CVE-2026-64827 has been assigned to this vulnerability.

• Credits:

Vulnerability discovered by Egidio Romano.