CVE-2025-49389 is a stored Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the WEN Solutions Notice Bar product up to version 3.1.3. Stored XSS occurs when malicious input is improperly neutralized and subsequently stored by the application, later being rendered in web pages without adequate sanitization or encoding. This allows an attacker to inject malicious scripts that execute in the context of users’ browsers when they view the affected Notice Bar content. The vulnerability arises from improper input validation and output encoding during web page generation, enabling attackers with at least low privileges (PR:L) and requiring user interaction (UI:R) to exploit it remotely (AV:N). The CVSS v3.1 base score is 6.5, indicating a medium severity level, with partial impacts on confidentiality, integrity, and availability (C:L/I:L/A:L). The scope is changed (S:C), meaning the vulnerability can affect components beyond the initially vulnerable module. Although no known exploits are currently in the wild and no patches have been linked yet, the vulnerability poses a risk of session hijacking, credential theft, defacement, or distribution of malware through malicious scripts injected into the Notice Bar interface. Since Notice Bar is a web-based notification tool, the vulnerability could be triggered when users interact with or view the compromised notification content, potentially affecting all users of the affected versions.

For European organizations using WEN Solutions Notice Bar, this vulnerability could lead to unauthorized access to sensitive user information, session tokens, or credentials through malicious script execution in users’ browsers. This can result in data breaches, reputational damage, and potential regulatory non-compliance under GDPR due to exposure of personal data. The integrity of displayed content can be compromised, misleading users or delivering malicious payloads. Availability impact is possible if injected scripts perform disruptive actions such as redirecting users or causing application instability. Organizations in sectors with high web presence, such as e-commerce, finance, and public services, are particularly at risk. The medium severity suggests that while exploitation requires some user interaction and privileges, the potential for lateral impact and cross-component compromise (scope changed) increases the threat surface. Given the absence of known exploits, proactive mitigation is critical to prevent exploitation once attackers develop weaponized payloads.

1. Immediate application of patches or updates from WEN Solutions once available is essential. 2. In the absence of official patches, implement strict input validation and output encoding on all user-supplied data rendered in the Notice Bar, using context-appropriate encoding (e.g., HTML entity encoding). 3. Employ Content Security Policy (CSP) headers to restrict script execution sources and reduce the impact of injected scripts. 4. Conduct thorough code reviews and penetration testing focused on XSS vectors within the Notice Bar implementation. 5. Limit privileges of users who can input content into the Notice Bar to reduce the risk of malicious input. 6. Monitor web application logs and user reports for suspicious behavior indicative of XSS exploitation attempts. 7. Educate users to be cautious about unexpected or suspicious notifications and interactions. 8. Consider deploying Web Application Firewalls (WAFs) with rules tuned to detect and block XSS payloads targeting Notice Bar endpoints. These measures, combined, will reduce the likelihood and impact of exploitation beyond generic advice.