CVE-2025-54046 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the QuanticaLabs Cost Calculator product up to version 7.4. Stored XSS occurs when malicious input is improperly neutralized and then stored by the application, later rendered in web pages without adequate sanitization. This allows an attacker to inject malicious scripts that execute in the context of other users' browsers when they view affected pages. The vulnerability arises from insufficient input validation or output encoding during web page generation, enabling attackers to embed arbitrary JavaScript code. Exploitation requires at least low privileges (PR:L) and user interaction (UI:R), but no physical access or elevated privileges beyond that. The CVSS v3.1 base score is 6.5 (medium severity), reflecting network attack vector (AV:N), low attack complexity (AC:L), partial privileges required, and a scope change (S:C) indicating that the vulnerability affects resources beyond the initially vulnerable component. The impact includes partial confidentiality, integrity, and availability loss, as malicious scripts can steal session tokens, manipulate page content, or perform actions on behalf of users. No known public exploits have been reported yet, and no patches are currently linked, indicating that mitigation may rely on vendor updates or user-side protections. The vulnerability is significant because Cost Calculator is a web-based tool often embedded in websites to provide pricing or cost estimation functionality, making it a potential vector for widespread exploitation if left unaddressed.

For European organizations, this vulnerability poses risks primarily to web applications integrating the QuanticaLabs Cost Calculator, especially those handling sensitive user data or financial transactions. Successful exploitation could lead to session hijacking, unauthorized actions, or data leakage, undermining user trust and potentially violating GDPR requirements for data protection. The scope change means that the vulnerability could affect multiple components or users beyond the initial application boundary, increasing the risk of lateral movement or broader compromise within enterprise environments. Organizations in sectors such as e-commerce, financial services, and public administration that rely on embedded cost calculators could face reputational damage, regulatory penalties, and operational disruptions. Additionally, the requirement for user interaction means phishing or social engineering campaigns could be used to trigger the exploit, increasing the attack surface. Given the medium severity and partial privileges needed, attackers with limited access could still leverage this flaw to escalate privileges or gain persistent footholds.

European organizations should prioritize the following specific actions: 1) Immediately audit all web properties for the presence of QuanticaLabs Cost Calculator versions up to 7.4 and isolate affected instances. 2) Implement strict input validation and output encoding on all user-supplied data fields within the calculator to neutralize malicious scripts, using context-aware escaping libraries such as OWASP Java Encoder or similar. 3) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of potential XSS payloads. 4) Monitor web application logs and user activity for unusual patterns indicative of XSS exploitation attempts. 5) Educate users and administrators about phishing risks that could trigger stored XSS attacks. 6) Engage with QuanticaLabs to obtain patches or updates addressing this vulnerability and apply them promptly once available. 7) Consider deploying Web Application Firewalls (WAFs) with custom rules to detect and block malicious payloads targeting this vulnerability. 8) Conduct regular security testing, including automated scanning and manual penetration testing focused on XSS vectors within the Cost Calculator integration.