CVE-2025-12290 is a cross-site scripting vulnerability identified in version 1.0 of the Suishang Enterprise-Level B2B2C Multi-User Mall System, a platform designed for multi-user e-commerce operations. The vulnerability exists in an unspecified functionality related to the /i/359 endpoint where the 'keywords' parameter is improperly sanitized, allowing an attacker to inject malicious JavaScript code. This flaw can be exploited remotely without any authentication, requiring only that a victim interacts with a crafted URL or input containing the malicious payload. The vulnerability is classified as medium severity with a CVSS 4.0 base score of 5.3, reflecting its moderate impact on confidentiality and integrity, limited impact on availability, and the need for user interaction. The vendor was notified but has not issued a patch or response, increasing the risk of exploitation as the details are publicly available. While no active exploitation has been reported, the presence of a public disclosure means attackers could develop exploits. The vulnerability could be leveraged to steal session cookies, perform phishing attacks, or manipulate the user interface, undermining trust in the affected e-commerce platform. Given the nature of the platform, attackers could target customers or administrators, potentially leading to broader compromise within affected organizations.

For European organizations using the Suishang Enterprise-Level B2B2C Multi-User Mall System, this XSS vulnerability poses risks primarily to the confidentiality and integrity of user data. Attackers exploiting this flaw could hijack user sessions, steal credentials, or inject malicious content that could lead to phishing or malware distribution. This could result in financial losses, reputational damage, and regulatory penalties under GDPR if personal data is compromised. The e-commerce nature of the platform means customer trust is critical; exploitation could lead to loss of customers and business disruption. Additionally, attackers might leverage this vulnerability as a foothold for further attacks within the organization's network. The lack of vendor response and patch availability increases the urgency for organizations to implement compensating controls. The impact is heightened in sectors with high online transaction volumes and sensitive customer data, common in European markets.

1. Implement strict input validation and sanitization on the 'keywords' parameter at the application level to neutralize malicious scripts. 2. Apply context-aware output encoding (e.g., HTML entity encoding) before rendering user-supplied data in web pages. 3. Deploy a Web Application Firewall (WAF) configured to detect and block common XSS attack patterns, specifically targeting the vulnerable endpoint. 4. Conduct thorough security testing, including automated and manual penetration testing focused on XSS vectors in the affected system. 5. Educate users and administrators about the risks of clicking untrusted links and recognizing phishing attempts. 6. Monitor web server logs for unusual requests to /i/359 with suspicious 'keywords' parameters. 7. If possible, isolate or restrict access to the vulnerable system until a vendor patch or official fix is available. 8. Consider implementing Content Security Policy (CSP) headers to reduce the impact of potential XSS exploitation by restricting script execution sources.