CVE-2025-52753 is a reflected Cross-site Scripting (XSS) vulnerability identified in the WordPress plugin 'Contact Form by Supsystic' up to version 1.7.35. The vulnerability arises from improper neutralization of user-supplied input during web page generation, allowing attackers to inject malicious scripts that are reflected back to users. This type of XSS does not require authentication but does require user interaction, such as clicking a crafted link or submitting a malicious form. The vulnerability affects the confidentiality, integrity, and availability of the affected web application by enabling attackers to execute arbitrary JavaScript in the context of the victim's browser. Potential impacts include session hijacking, defacement, redirection to malicious sites, or execution of unauthorized actions on behalf of the user. The CVSS v3.1 base score is 7.1, reflecting network attack vector, low attack complexity, no privileges required, user interaction needed, and a scope change with low impact on confidentiality, integrity, and availability. No known exploits are currently in the wild, but the vulnerability is publicly disclosed and should be addressed promptly. The lack of an official patch link suggests that a fix may be forthcoming. The plugin is widely used in WordPress sites for contact form functionality, making the attack surface significant. The vulnerability is particularly concerning for public-facing websites that rely on this plugin to collect user input, as attackers can craft URLs or form submissions to exploit the flaw.

For European organizations, this vulnerability poses a significant risk to websites using the Contact Form by Supsystic plugin, especially those with high traffic or handling sensitive user data. Exploitation can lead to theft of user credentials, session tokens, or personal information, undermining user trust and potentially violating GDPR requirements for data protection. The reflected XSS can also be used to deliver phishing attacks or malware, increasing the risk of broader compromise. Website integrity and availability may be affected through defacement or denial-of-service conditions triggered by malicious scripts. Organizations in sectors such as e-commerce, government, healthcare, and education, which often rely on contact forms for user interaction, are particularly vulnerable. The reputational damage and potential regulatory penalties from data breaches or misuse of personal data can be substantial. Since the vulnerability requires user interaction, social engineering campaigns targeting European users could amplify the impact. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as exploit code may emerge following public disclosure.

1. Monitor the official Supsystic plugin repository and security advisories for the release of a patch addressing CVE-2025-52753 and apply it immediately upon availability. 2. Until an official patch is released, implement strict input validation and output encoding on all user-supplied data processed by the contact form, either via custom code or security plugins that sanitize inputs. 3. Deploy a Web Application Firewall (WAF) with rules designed to detect and block reflected XSS attack patterns targeting the contact form endpoints. 4. Educate website administrators and users about the risks of clicking on suspicious links or submitting untrusted data through contact forms. 5. Regularly audit and update all WordPress plugins and themes to minimize exposure to known vulnerabilities. 6. Consider temporarily disabling the Contact Form by Supsystic plugin if the risk outweighs the operational need until a patch is available. 7. Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 8. Conduct penetration testing focused on XSS vulnerabilities to verify the effectiveness of mitigations.