CVE-2025-59556 is a reflected Cross-site Scripting (XSS) vulnerability identified in the skygroup GoStore e-commerce platform, affecting all versions prior to 1.6.4. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, which allows malicious actors to inject executable scripts into HTTP responses. When a victim interacts with a crafted URL or input, the injected script executes within their browser context, potentially enabling session hijacking, credential theft, or unauthorized actions on behalf of the user. The vulnerability requires no authentication but does require user interaction, such as clicking a malicious link. The CVSS 3.1 base score of 7.1 reflects a high severity, with network attack vector, low attack complexity, no privileges required, user interaction required, and a scope change indicating that the vulnerability can impact components beyond the initially vulnerable one. Confidentiality, integrity, and availability impacts are all rated low to partial, meaning attackers can gain some unauthorized access or cause limited disruption. Although no public exploits are currently known, the vulnerability is publicly disclosed and should be considered a significant risk. The lack of available patches at the time of disclosure necessitates immediate interim mitigations. This vulnerability is particularly relevant to organizations running GoStore for online retail, as exploitation could compromise customer data and trust. The reflected XSS nature means that the attack is transient and requires social engineering to lure victims to malicious URLs. However, the scope change in the CVSS vector suggests that the impact could extend beyond the immediate web application, potentially affecting other integrated systems or user sessions.

For European organizations, the impact of CVE-2025-59556 is considerable, especially for those operating e-commerce platforms or online retail services using GoStore. Successful exploitation could lead to theft of customer credentials, session hijacking, and unauthorized transactions, undermining customer trust and causing financial losses. The partial compromise of confidentiality and integrity could expose sensitive personal data, potentially triggering regulatory penalties under GDPR. Availability impacts, though low, could disrupt service continuity if attackers leverage the vulnerability for denial-of-service or to inject disruptive scripts. The reflected XSS nature means attacks require user interaction, but phishing campaigns could be used to target customers or employees. Given the critical role of e-commerce in European economies, especially in countries with large retail sectors, this vulnerability could have cascading effects on business operations and reputation. Additionally, attackers could use the vulnerability as a foothold for further attacks within the network, increasing overall risk exposure. The absence of known exploits in the wild currently provides a window for mitigation, but the public disclosure increases the likelihood of future exploitation attempts.

European organizations using GoStore should immediately inventory affected versions and plan prompt upgrades to version 1.6.4 or later once patches are released by skygroup. Until patches are available, implement strict input validation and sanitization on all user-supplied data, especially in URL parameters and form inputs, to prevent malicious script injection. Deploy Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. Employ web application firewalls (WAFs) with rules targeting reflected XSS patterns to detect and block exploit attempts. Conduct user awareness training to reduce the risk of phishing attacks that could deliver malicious URLs. Monitor web server and application logs for unusual request patterns indicative of exploitation attempts. Additionally, review session management practices to ensure that session tokens are protected via HttpOnly and Secure flags to mitigate session hijacking risks. Finally, coordinate with incident response teams to prepare for potential exploitation scenarios and ensure rapid containment and remediation.