CVE-2025-48489 is a medium-severity Cross-Site Scripting (XSS) vulnerability affecting FreeScout, a free and self-hosted help desk and shared mailbox application. The vulnerability exists in versions prior to 1.8.180 due to improper neutralization of input during web page generation, specifically insufficient data validation and sanitization when processing user-supplied data. This flaw allows an attacker to inject malicious scripts into web pages viewed by other users. The vulnerability is categorized under CWE-79, which pertains to improper neutralization of input leading to XSS. The CVSS 4.0 base score is 4.6, indicating a medium impact with network attack vector, high attack complexity, no privileges required but low privileges needed, and user interaction required. The vulnerability does not impact confidentiality, integrity, or availability directly but can lead to session hijacking, credential theft, or unauthorized actions performed in the context of the victim user. The issue has been patched in FreeScout version 1.8.180, and no known exploits are currently reported in the wild. The vulnerability requires user interaction and has a high scope complexity, meaning exploitation is not trivial but possible under certain conditions. Since FreeScout is self-hosted, the exposure depends on the deployment and access controls implemented by the administrators.

For European organizations using FreeScout, this vulnerability could lead to targeted attacks where malicious actors inject scripts to steal session cookies, perform actions on behalf of legitimate users, or deliver further malware. Given FreeScout’s role in managing customer support and shared mailboxes, exploitation could compromise sensitive customer data and internal communications. Organizations in sectors with strict data protection regulations like GDPR could face compliance risks and reputational damage if such an attack leads to data leakage. The medium CVSS score reflects moderate risk, but the impact could be elevated if attackers combine this with social engineering to increase user interaction. Since FreeScout is often used by SMEs and public sector organizations in Europe for cost-effective help desk solutions, the risk is non-negligible. The lack of known exploits suggests a window of opportunity for proactive patching before widespread attacks occur.

European organizations should immediately upgrade FreeScout installations to version 1.8.180 or later to apply the official patch that addresses this XSS vulnerability. Additionally, administrators should implement strict Content Security Policies (CSP) to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. Input validation and output encoding should be reviewed and enhanced where possible, especially for any custom plugins or integrations with FreeScout. User education to recognize phishing attempts and suspicious links can reduce the likelihood of successful exploitation requiring user interaction. Network segmentation and limiting access to the FreeScout instance to trusted users and IP ranges will also reduce exposure. Regular security audits and monitoring for unusual activity or script injections in the application logs are recommended to detect attempted exploitation early.