CVE-2025-52749 identifies a reflected Cross-site Scripting (XSS) vulnerability in the Activity Track Uji Countdown application, specifically in versions up to 2.3.3. The vulnerability stems from improper neutralization of user-supplied input during the dynamic generation of web pages, which allows attackers to inject malicious JavaScript code. When a victim interacts with a crafted URL or input, the malicious script executes within their browser context, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the user. The vulnerability is exploitable remotely over the network without requiring any privileges (AV:N, PR:N), but it does require user interaction (UI:R), such as clicking a malicious link. The scope is changed (S:C), meaning the vulnerability can affect resources beyond the vulnerable component, impacting confidentiality, integrity, and availability (C:L/I:L/A:L). Although no known exploits have been reported in the wild, the high CVSS score of 7.1 reflects the significant risk posed by this vulnerability. No patches or fixes have been published yet, increasing the urgency for organizations to implement interim mitigations. The vulnerability affects all deployments of Uji Countdown up to version 2.3.3, but the exact affected versions are not fully enumerated. The flaw is categorized under improper input neutralization, a common web application security issue that can be mitigated by proper input validation and output encoding. The vulnerability was reserved in June 2025 and published in October 2025, indicating recent discovery and disclosure.

For European organizations, this vulnerability presents a substantial risk to web applications utilizing the Uji Countdown product. Exploitation can lead to unauthorized access to user sessions, theft of sensitive data, and manipulation of application behavior, which can disrupt business operations and damage reputation. Organizations in sectors such as finance, healthcare, and critical infrastructure that rely on Uji Countdown for activity tracking or countdown functionalities may face increased exposure. The reflected XSS nature means phishing campaigns could be used to trick users into executing malicious scripts, amplifying the threat. Additionally, the scope change indicates that the attack could affect multiple components or user accounts, potentially leading to broader compromise within an organization. The lack of available patches means that organizations must rely on compensating controls, increasing operational overhead and risk. The vulnerability could also be leveraged as a foothold for further attacks, including privilege escalation or malware deployment, especially if combined with other vulnerabilities.

1. Implement strict input validation on all user-supplied data, ensuring that inputs are sanitized and validated against expected formats before processing. 2. Apply proper output encoding/escaping techniques when rendering user input in web pages, particularly in HTML, JavaScript, and URL contexts, to prevent script injection. 3. Deploy Web Application Firewalls (WAFs) with custom rules to detect and block malicious payloads targeting the Uji Countdown application. 4. Educate users and administrators about the risks of clicking unknown or suspicious links to reduce the likelihood of successful phishing attempts exploiting this vulnerability. 5. Monitor web server and application logs for unusual request patterns or error messages indicative of attempted XSS exploitation. 6. Prepare for timely patching by tracking vendor updates and applying security patches immediately upon release. 7. Consider implementing Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 8. Conduct regular security assessments and penetration testing focused on input handling and XSS vulnerabilities in the Uji Countdown deployment environment.