CVE-2025-66093 identifies a DOM-based Cross-site Scripting (XSS) vulnerability in the hupe13 Extensions for Leaflet Map, a popular JavaScript library extension used for interactive map visualizations. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, allowing malicious scripts to be injected and executed within the victim's browser environment. This type of XSS is particularly dangerous because it exploits client-side code, making detection and mitigation more challenging. The affected versions include all releases up to and including 4.8. Although no official patches or exploit code are currently available, the vulnerability's presence in a widely used mapping extension raises concerns about potential attacks targeting web applications that incorporate this library. Attackers could leverage this flaw to steal cookies, perform session hijacking, or execute arbitrary actions on behalf of authenticated users. The vulnerability does not require authentication or user interaction beyond visiting a crafted URL or page, increasing its risk profile. The absence of a CVSS score necessitates an expert severity assessment, which considers the impact on confidentiality, integrity, and availability, as well as exploitation complexity and affected scope. Given the nature of DOM-based XSS and the widespread use of Leaflet Map extensions in web applications, the threat is significant. Organizations using this extension should monitor for updates from the vendor hupe13 and prepare to deploy patches promptly. In the interim, implementing strict input validation, sanitization, and Content Security Policies (CSP) can reduce the attack surface. Additionally, security teams should audit web applications for vulnerable endpoints and monitor logs for suspicious script execution patterns.

For European organizations, the impact of CVE-2025-66093 can be substantial, especially for those relying on web applications that integrate the hupe13 Extensions for Leaflet Map for geospatial data visualization and interactive mapping. Successful exploitation could lead to unauthorized access to user sessions, theft of sensitive data such as authentication tokens or personal information, and potential manipulation of user interactions within the affected web applications. This could undermine user trust, lead to regulatory non-compliance (e.g., GDPR violations), and cause reputational damage. Sectors such as government, transportation, urban planning, and utilities, which often use mapping solutions, may face heightened risks. The vulnerability could also serve as a foothold for further attacks within organizational networks if attackers leverage stolen credentials or session tokens. Since the vulnerability does not require authentication or complex user interaction, the attack surface is broad, increasing the likelihood of exploitation if unmitigated. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as public disclosure may prompt attackers to develop exploits rapidly.

1. Monitor hupe13 vendor communications and security advisories closely to apply official patches or updates as soon as they become available. 2. Implement strict input validation and sanitization on all user-supplied data that interacts with the Leaflet Map extensions to prevent injection of malicious scripts. 3. Deploy and enforce a robust Content Security Policy (CSP) that restricts the execution of inline scripts and limits sources of executable code to trusted domains. 4. Conduct thorough code reviews and security testing of web applications using the affected Leaflet Map extensions to identify and remediate any unsafe DOM manipulations. 5. Utilize web application firewalls (WAFs) with custom rules to detect and block suspicious payloads targeting this vulnerability. 6. Educate developers and security teams about the risks of DOM-based XSS and secure coding practices specific to client-side JavaScript. 7. Monitor application logs and user activity for signs of unusual script execution or session anomalies that could indicate exploitation attempts. 8. Consider isolating or sandboxing map components within web applications to limit the impact of potential script execution.