CVE-2025-31917 is a high-severity reflected Cross-site Scripting (XSS) vulnerability identified in the LambertGroup Universal Video Player, affecting versions up to 3.8.3. This vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79. Specifically, the Universal Video Player fails to adequately sanitize or encode user-supplied input before reflecting it in the web page output. As a result, an attacker can craft malicious URLs or input parameters that, when processed by the vulnerable player, execute arbitrary JavaScript code in the context of the victim's browser. The CVSS v3.1 score of 7.1 reflects the vulnerability's characteristics: it is remotely exploitable over the network (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R) such as clicking a malicious link. The scope is changed (S:C), indicating that exploitation can affect resources beyond the vulnerable component. The impact includes low confidentiality, integrity, and availability impacts individually, but combined they can lead to significant session hijacking, credential theft, or unauthorized actions on behalf of the user. No known exploits are currently in the wild, and no patches have been linked yet. The vulnerability was reserved in early April 2025 and published in June 2025, indicating recent discovery. The Universal Video Player is a web-based media player component used to embed and play video content on websites, often integrated into web portals, media sites, and potentially enterprise intranet applications. The reflected XSS can be leveraged by attackers to steal session cookies, perform phishing attacks, or deliver malware payloads via the victim's browser, compromising user accounts and data confidentiality.

For European organizations, this vulnerability poses a significant risk especially for those relying on the LambertGroup Universal Video Player in their web infrastructure, including media companies, educational platforms, and corporate intranets. Successful exploitation could lead to unauthorized access to user sessions, data leakage, and potential lateral movement within internal networks if the player is used in internal applications. Given the scope change in the CVSS vector, attackers might leverage this vulnerability to affect other components or services beyond the player itself. The confidentiality and integrity of user data are at risk, which could lead to regulatory compliance issues under GDPR if personal data is compromised. Additionally, the availability impact, while low individually, could be escalated through chained attacks causing service disruptions. The requirement for user interaction means phishing or social engineering campaigns could be used to trick users into triggering the exploit, increasing the attack surface. Organizations with high web traffic and user engagement are particularly vulnerable to reputational damage and operational disruption from such attacks.

Organizations should prioritize the following mitigations: 1) Immediate review and audit of all web applications and portals using LambertGroup Universal Video Player to identify affected versions. 2) Apply any available patches or updates from LambertGroup as soon as they are released; if no patch is available, consider temporary removal or replacement of the player with alternative secure video players. 3) Implement strict Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. 4) Employ input validation and output encoding on all user-supplied data, especially parameters reflected in URLs or page content, to prevent injection of malicious scripts. 5) Educate users about phishing risks and suspicious links to reduce the likelihood of user interaction exploitation. 6) Monitor web server logs and network traffic for unusual requests or patterns indicative of attempted XSS exploitation. 7) Use web application firewalls (WAFs) with updated signatures to detect and block XSS attack vectors targeting this vulnerability. 8) Conduct penetration testing focused on XSS vulnerabilities to verify the effectiveness of mitigations.