CVE-2025-48107 is a high-severity reflected Cross-site Scripting (XSS) vulnerability identified in the undsgn Uncode product. The vulnerability is classified under CWE-79, which involves improper neutralization of input during web page generation. Specifically, this vulnerability allows an attacker to inject malicious scripts into web pages generated by the Uncode product, which are then reflected back to users. This reflected XSS does not require authentication (PR:N) but does require user interaction (UI:R), such as clicking a crafted link or visiting a maliciously constructed URL. The vulnerability has a CVSS 3.1 base score of 7.1, indicating a high impact with network attack vector (AV:N), low attack complexity (AC:L), and a scope change (S:C), meaning the vulnerability affects resources beyond the initially vulnerable component. The impact includes partial loss of confidentiality, integrity, and availability (C:L/I:L/A:L), which is typical for reflected XSS attacks where attackers can steal session cookies, perform actions on behalf of users, or cause denial of service through script execution. No specific affected versions are listed, which suggests the vulnerability might affect all current versions of Uncode until patched. There are no known exploits in the wild at the time of publication, and no patches have been linked yet. The vulnerability was reserved in May 2025 and published in September 2025, indicating recent discovery and disclosure. Reflected XSS vulnerabilities are commonly exploited via phishing or social engineering to trick users into executing malicious scripts, potentially leading to account compromise or unauthorized actions within web applications using Uncode.

For European organizations using the undsgn Uncode product, this vulnerability poses a significant risk, especially for those relying on Uncode for web content management or site generation. The reflected XSS can lead to session hijacking, credential theft, or unauthorized actions performed in the context of authenticated users. This can result in data breaches, reputational damage, and compliance violations under regulations such as GDPR, which mandates protection of personal data. Since the attack vector is network-based and requires no authentication, any publicly accessible web application using Uncode is vulnerable to exploitation by remote attackers. The scope change indicates that the vulnerability could impact additional components or user privileges beyond the initial vulnerability, increasing the potential damage. European organizations in sectors such as finance, healthcare, government, and e-commerce, which often have high-value targets and sensitive data, could be particularly impacted. Additionally, reflected XSS can be used as a stepping stone for more complex attacks, including delivering malware or conducting phishing campaigns targeting European users.

To mitigate this vulnerability, European organizations should first monitor undsgn's official channels for patches or updates addressing CVE-2025-48107 and apply them promptly once available. In the interim, organizations should implement strict input validation and output encoding on all user-supplied data reflected in web pages generated by Uncode. Employing Content Security Policy (CSP) headers can help restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. Web Application Firewalls (WAFs) configured to detect and block reflected XSS payloads can provide additional protection. Organizations should also conduct thorough security testing, including automated and manual penetration testing focused on XSS vectors within Uncode-powered applications. User awareness training to recognize phishing attempts that might exploit this vulnerability is critical. Finally, logging and monitoring for unusual web requests or script injection attempts can help detect exploitation attempts early.