CVE-2026-27504 is a reflected cross-site scripting (XSS) vulnerability classified under CWE-79, affecting SVXportal versions 2.5 and earlier. The vulnerability arises from improper neutralization of user input in the radiomobile_front.php script, specifically through the stationid query parameter. When an authenticated administrator visits a maliciously crafted URL containing a manipulated stationid parameter, the application fails to sanitize this input before embedding it into a hidden input field within the web page. This allows an attacker to inject arbitrary JavaScript code that executes in the administrator's browser context. Because the script runs with the administrator's privileges, it can hijack sessions, steal cookies, or perform unauthorized administrative actions. The vulnerability requires the administrator to click or visit the malicious link, making user interaction necessary. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, and low scope impact. Although no public exploits are known, the vulnerability poses a significant risk due to the high privileges of the targeted user. No official patches or mitigations have been released by the vendor as of the publication date. This vulnerability highlights the critical importance of input validation and output encoding in web applications, especially for parameters embedded in HTML elements.

The primary impact of CVE-2026-27504 is the potential compromise of administrator accounts within SVXportal deployments. Successful exploitation can lead to session hijacking, unauthorized administrative actions, and potentially full control over the affected portal. This could result in unauthorized configuration changes, data leakage, or disruption of services managed through SVXportal. Since the vulnerability targets administrators, the confidentiality, integrity, and availability of the system are at risk. Organizations relying on SVXportal for critical communications or infrastructure management could face operational disruptions and reputational damage. The requirement for user interaction (administrator clicking a malicious link) somewhat limits the attack surface but does not eliminate the risk, especially in environments where phishing or social engineering attacks are common. The absence of known exploits in the wild suggests limited current exploitation but also indicates the need for proactive defense before attackers develop weaponized payloads.

To mitigate CVE-2026-27504, organizations should immediately implement the following measures: 1) Educate administrators to avoid clicking on suspicious or untrusted links, especially those containing query parameters. 2) Employ web application firewalls (WAFs) with rules designed to detect and block reflected XSS payloads targeting the stationid parameter. 3) Restrict administrative access to SVXportal interfaces to trusted networks or VPNs to reduce exposure. 4) Monitor administrator sessions for unusual activity that could indicate session hijacking or unauthorized actions. 5) If possible, apply manual input validation or output encoding in the radiomobile_front.php script to sanitize the stationid parameter, such as encoding special characters before embedding in HTML. 6) Regularly check for vendor updates or patches addressing this vulnerability and apply them promptly once available. 7) Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts within the administrator interface. These steps go beyond generic advice by focusing on immediate risk reduction and compensating controls until a vendor patch is released.