CVE-2025-52763 is a reflected Cross-site Scripting (XSS) vulnerability identified in NickDuncan's Nifty Backups software, affecting versions up to and including 1.08. The root cause is improper neutralization of user-supplied input during web page generation, which allows attackers to inject malicious JavaScript code into web pages viewed by other users. This vulnerability is classified as reflected XSS, meaning the malicious payload is embedded in a URL or request and reflected back in the server's response without proper sanitization. The CVSS v3.1 base score is 7.1, indicating high severity, with an attack vector of network (remote exploitation), low attack complexity, no privileges required, but user interaction is necessary (e.g., victim clicking a malicious link). The scope is changed, meaning the vulnerability affects components beyond the initially vulnerable component, potentially impacting the entire application or user session. The impact includes partial loss of confidentiality (e.g., theft of session cookies), integrity (e.g., unauthorized actions performed on behalf of the user), and availability (e.g., disruption of service through script-based attacks). No patches or known exploits are currently documented, but the vulnerability's nature makes it a likely target for phishing or social engineering campaigns. The vulnerability was reserved in June 2025 and published in October 2025. Given that Nifty Backups is a backup management tool, exploitation could lead to unauthorized access or manipulation of backup configurations or data, increasing the risk to organizational data integrity and availability.

For European organizations, the impact of CVE-2025-52763 can be significant, especially for those relying on Nifty Backups for critical backup and recovery operations. Successful exploitation could allow attackers to execute arbitrary scripts in the context of an authenticated user, potentially leading to session hijacking, credential theft, or unauthorized changes to backup configurations. This could compromise the integrity and availability of backup data, critical for business continuity and disaster recovery. Additionally, attackers could leverage this vulnerability to pivot into broader network attacks or data exfiltration. The requirement for user interaction means phishing or social engineering campaigns could be effective vectors. Organizations in sectors with stringent data protection regulations, such as finance, healthcare, and government, face heightened risks of regulatory non-compliance and reputational damage if exploited. The reflected XSS nature also poses risks to end users and administrators accessing the backup management interface, potentially undermining trust and operational security.

To mitigate CVE-2025-52763, organizations should first verify if they are running affected versions of Nifty Backups (<= 1.08) and prioritize upgrading to a patched version once available. In the absence of an official patch, implement strict input validation and output encoding on all user-supplied data reflected in web pages to neutralize malicious scripts. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. Educate users and administrators about the risks of clicking on suspicious links or opening untrusted URLs related to the backup management interface. Network-level protections such as Web Application Firewalls (WAFs) can be configured to detect and block common XSS attack patterns targeting the application. Regularly audit and monitor logs for unusual access patterns or script injection attempts. Additionally, isolate the backup management interface within secure network segments and enforce multi-factor authentication to reduce the risk of unauthorized access. Finally, maintain up-to-date backups and test recovery procedures to minimize impact in case of compromise.