CVE-2025-70891 identifies a stored cross-site scripting (XSS) vulnerability in the Phpgurukul Cyber Cafe Management System version 1.0. The vulnerability resides in the user management module, where the application fails to properly sanitize or encode user-supplied input submitted through the 'uadd' parameter in the add-users.php endpoint. An attacker with valid authentication can inject arbitrary JavaScript code that is persistently stored in the backend database. This malicious script executes when a privileged user accesses the view-allusers.php page and clicks the View button, triggering the payload. The vulnerability leverages CWE-79 (Improper Neutralization of Input During Web Page Generation), a common web application security flaw. The CVSS v3.1 score of 6.1 indicates a medium severity, with an attack vector of network (remote), low attack complexity, no privileges required, but requiring user interaction. The scope is changed, meaning the vulnerability can affect resources beyond the vulnerable component. The impact affects confidentiality and integrity but not availability. Although no public exploits are currently known, the persistent nature of the XSS could allow session hijacking, credential theft, or further exploitation such as privilege escalation or lateral movement within the application. The vulnerability is particularly concerning in environments where privileged users frequently access the user management interface, as the injected script executes in their browser context.

For European organizations, especially those operating cyber cafes or managing public access computing environments using the Phpgurukul Cyber Cafe Management System, this vulnerability poses a significant risk. Exploitation could lead to theft of privileged user credentials, session hijacking, or unauthorized actions performed with elevated privileges, potentially compromising sensitive user data and administrative controls. The persistent nature of the XSS means that once injected, the malicious code remains active until removed, increasing exposure duration. This could facilitate further attacks such as deploying malware or pivoting within the network. Given the medium severity and requirement for authentication, the threat is more relevant to insider attackers or compromised user accounts. However, the impact on confidentiality and integrity of data could disrupt business operations and damage trust, especially under strict European data protection regulations like GDPR. Organizations may face regulatory penalties if user data is compromised due to inadequate security controls.

To mitigate CVE-2025-70891, organizations should implement strict input validation and output encoding on all user-supplied data, particularly the 'uadd' parameter in add-users.php. Employ context-aware encoding to neutralize scripts before rendering in the browser. Conduct thorough code reviews and security testing focused on the user management module. Restrict user privileges to the minimum necessary, ensuring that only trusted users can add or modify user accounts. Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts. Regularly audit and sanitize the database to remove any injected malicious scripts. Additionally, monitor user activity logs for suspicious behavior indicative of exploitation attempts. If possible, upgrade or patch the application once vendor fixes become available. Educate privileged users about the risks of clicking untrusted links or buttons within the management interface. Finally, consider deploying web application firewalls (WAFs) with rules to detect and block XSS payloads targeting this endpoint.