CVE-2024-25207 identifies a cross-site scripting (XSS) vulnerability in the Barangay Population Monitoring System version 1.0, specifically within the Add Resident functionality located at /barangay-population-monitoring-system/masterlist.php. The vulnerability arises from improper input validation or sanitization of the Contact Number parameter, allowing an attacker to inject arbitrary web scripts or HTML code. When a crafted payload is submitted via this parameter, it can be executed in the context of the victim's browser session. This type of vulnerability is classified under CWE-79 and typically enables attackers to perform actions such as session hijacking, defacement, or redirecting users to malicious sites. The CVSS v3.1 base score is 5.4, indicating a medium severity level. The vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N) reveals that the attack can be performed remotely over the network with low attack complexity, requires the attacker to have some privileges (PR:L) and user interaction (UI:R), and impacts confidentiality and integrity with a scope change (S:C). There is no known exploit in the wild, and no patches have been published yet. The vulnerability affects a niche application likely used for local population data management, which may be deployed in specific administrative or governmental contexts.

For European organizations, the impact of this XSS vulnerability depends largely on whether the Barangay Population Monitoring System or similar software is in use within local government units or agencies managing population data. If deployed, exploitation could lead to unauthorized disclosure of sensitive resident information, manipulation of data integrity, or phishing attacks targeting administrative users. The scope change in the CVSS vector suggests that exploitation could affect other components or user sessions beyond the initial vulnerable parameter, potentially leading to broader compromise within the system. Given the nature of population monitoring systems, any data leakage or manipulation could undermine public trust and disrupt administrative operations. However, since the product appears to be region-specific (Barangay is a Filipino administrative division), direct impact on European organizations may be limited unless similar software or components are used. The medium severity rating reflects moderate risk but highlights the need for vigilance in environments where this system or analogous applications are deployed.

To mitigate this vulnerability, organizations should implement strict input validation and output encoding on all user-supplied data, especially the Contact Number field in the Add Resident function. Employing a whitelist approach for input validation (e.g., allowing only digits and specific formatting characters for phone numbers) can prevent injection of malicious scripts. Additionally, applying context-aware output encoding (HTML entity encoding) before rendering user input in web pages is critical. Web application firewalls (WAFs) can be configured to detect and block common XSS payloads targeting this endpoint. Since no official patch is available, organizations should consider isolating or restricting access to the vulnerable module, enforcing least privilege principles for users with access to the Add Resident function, and conducting regular security audits and penetration testing to identify similar vulnerabilities. User education to recognize phishing attempts resulting from XSS exploitation can also reduce impact. Monitoring logs for unusual input patterns or error messages related to the vulnerable parameter can aid in early detection of exploitation attempts.