CVE-2025-8153 is a Cross-site Scripting (XSS) vulnerability identified in NEC Corporation's UNIVERGE IX product line, affecting multiple versions ranging from 9.5 up to 10.11.6 and specific versions of UNIVERGE IX-R/IX-V. The vulnerability arises due to improper neutralization of input during web page generation, classified under CWE-79. This flaw allows an attacker to inject arbitrary scripts that execute in the context of a user's browser when interacting with the affected web interface. The vulnerability does not require authentication (AV:N), has low attack complexity (AC:L), and no privileges or user interaction are needed for exploitation (AT:N, PR:N, UI:A). The CVSS 4.0 base score is 5.1, indicating a medium severity level. The impact primarily concerns confidentiality and integrity, as malicious scripts could steal session tokens, perform unauthorized actions, or manipulate displayed content. Availability impact is minimal. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability affects the web management interface of UNIVERGE IX, a communication platform used in enterprise environments for unified communications and collaboration.

For European organizations using NEC UNIVERGE IX systems, this vulnerability poses a risk of session hijacking, credential theft, or unauthorized command execution via malicious script injection. Given that UNIVERGE IX is often deployed in enterprise telephony and communication infrastructures, exploitation could lead to compromised user accounts, data leakage, and disruption of communication services. The medium severity score reflects that while the vulnerability is exploitable remotely without authentication, it requires user interaction (e.g., clicking a crafted link or visiting a malicious page). This could facilitate targeted phishing campaigns against employees, potentially impacting confidentiality and operational integrity. Organizations in sectors with high communication demands such as finance, government, and critical infrastructure may face increased risks. However, the absence of known exploits and patches suggests a window for proactive mitigation before active exploitation occurs.

1. Immediate mitigation should include restricting access to the UNIVERGE IX web management interface to trusted networks and IP addresses, minimizing exposure to potential attackers. 2. Implement strict Content Security Policy (CSP) headers on the web interface to limit the execution of unauthorized scripts. 3. Employ web application firewalls (WAFs) with rules tailored to detect and block XSS payloads targeting the UNIVERGE IX interface. 4. Educate users about phishing risks and the dangers of clicking unknown links, as user interaction is required for exploitation. 5. Monitor network traffic and logs for unusual activity or attempts to inject scripts. 6. Coordinate with NEC for timely patch deployment once available; in the interim, consider virtual patching techniques. 7. Conduct regular security assessments and penetration testing focused on the UNIVERGE IX environment to identify and remediate any related weaknesses.