CVE-2025-8976 is a cross-site scripting (XSS) vulnerability identified in the givanz Vvveb product, specifically affecting versions 1.0.0 through 1.0.5. The vulnerability resides in the /vadmin123/index.php endpoint, within the module parameter 'content/post' and type 'post'. An attacker can remotely exploit this flaw by injecting malicious scripts into the vulnerable parameter, which are then executed in the context of the victim's browser. This can lead to unauthorized actions such as session hijacking, credential theft, or the delivery of further malicious payloads. The vulnerability requires no authentication but does require user interaction (e.g., a victim visiting a crafted URL or page). The CVSS 4.0 score is 5.1 (medium severity), reflecting a network attack vector with low complexity and no privileges required, but with user interaction needed. The vulnerability does not impact confidentiality directly but has limited impact on integrity and availability. The vendor has released version 1.0.6 to address this issue, recommending immediate upgrade to mitigate risk. No known exploits are currently observed in the wild, but public disclosure increases the risk of exploitation attempts.

For European organizations using givanz Vvveb versions 1.0.0 to 1.0.5, this XSS vulnerability poses a moderate risk. Successful exploitation could allow attackers to execute arbitrary scripts in users' browsers, potentially leading to session hijacking, unauthorized actions, or phishing attacks within the affected web application. This could compromise user data integrity and trust, disrupt normal operations, and lead to reputational damage. Organizations relying on Vvveb for content management or web administration may face targeted attacks, especially if the affected endpoint is exposed to the internet. The risk is heightened in sectors with sensitive data or regulatory compliance requirements (e.g., GDPR), where data leakage or unauthorized access could result in legal and financial penalties. However, the requirement for user interaction and the medium severity limit the overall impact compared to more critical vulnerabilities.

1. Immediate upgrade of givanz Vvveb to version 1.0.6 or later, which contains the patch for this XSS vulnerability. 2. Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 3. Conduct thorough input validation and output encoding on all user-supplied data, especially in the affected module and parameters, to prevent injection of malicious scripts. 4. Limit access to the /vadmin123/index.php endpoint by IP whitelisting or VPN access to reduce exposure. 5. Educate users and administrators about the risks of clicking on suspicious links or interacting with untrusted content. 6. Monitor web server logs and application behavior for unusual requests or signs of attempted exploitation. 7. Employ web application firewalls (WAF) with rules tuned to detect and block XSS attack patterns targeting the vulnerable endpoint.