CVE-2025-58983 is a medium-severity vulnerability classified under CWE-79, which pertains to Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting (XSS). This vulnerability affects the software product "Include Me" developed by Stefano Lissa, specifically versions up to 1.3.2. The vulnerability is a Stored XSS, meaning that malicious input submitted by an attacker is persistently stored by the application and later rendered in web pages viewed by other users without proper sanitization or encoding. This flaw allows an attacker with high privileges (as indicated by the CVSS vector requiring PR:H) and requiring user interaction (UI:R) to inject malicious scripts that execute in the context of other users' browsers. The CVSS score of 5.9 reflects a medium severity level, with impacts on confidentiality, integrity, and availability, albeit limited in scope and requiring certain conditions for exploitation. The vulnerability has a scope of changed (S:C), indicating that exploitation affects resources beyond the vulnerable component. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on September 9, 2025, and was reserved a few days earlier. The attack vector is network-based (AV:N), with low attack complexity (AC:L), but requires high privileges and user interaction, which somewhat limits the ease of exploitation. Stored XSS vulnerabilities can lead to session hijacking, defacement, phishing, or distribution of malware, depending on the context of the affected application and the privileges of the attacker.

For European organizations using the Include Me software, this vulnerability poses a risk of persistent cross-site scripting attacks that can compromise user sessions, steal sensitive data, or manipulate displayed content. Given the requirement for high privileges to exploit, the threat is more relevant to internal users or administrators who have access to input fields that are stored and rendered. The impact on confidentiality, integrity, and availability is moderate but can escalate if attackers leverage the XSS to perform further attacks such as privilege escalation or lateral movement. Organizations in sectors with high regulatory requirements for data protection, such as finance, healthcare, and government, may face compliance risks if user data is exposed or manipulated. Additionally, the scope change indicates that the vulnerability could affect multiple components or users beyond the initially compromised module, increasing the potential damage. The lack of known exploits in the wild suggests that immediate risk is moderate, but proactive mitigation is essential to prevent future exploitation. European organizations should also consider the reputational damage and operational disruption that could result from successful attacks leveraging this vulnerability.

To mitigate CVE-2025-58983, European organizations should implement the following specific measures: 1) Immediately review and restrict high-privilege user access to the Include Me application to minimize the risk of malicious input submission. 2) Apply strict input validation and output encoding on all user-supplied data, especially in stored content rendered on web pages, using context-appropriate encoding libraries. 3) Monitor and audit logs for unusual input patterns or attempts to inject scripts, focusing on users with elevated privileges. 4) Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing the application. 5) Segregate the Include Me application environment to limit the scope of potential compromise and prevent lateral movement. 6) Engage with the vendor or community to obtain patches or updates as soon as they become available, and test these in controlled environments before deployment. 7) Educate administrators and users with high privileges about the risks of XSS and safe input handling practices. 8) Consider deploying Web Application Firewalls (WAF) with rules tuned to detect and block XSS payloads targeting Include Me. These targeted actions go beyond generic advice by focusing on privilege management, monitoring, and layered defenses tailored to the characteristics of this vulnerability.