CVE-2025-58412 is a cross-site scripting (XSS) vulnerability identified in Fortinet's FortiADC product, versions 7.2.0, 7.4.0, 7.6.0 through 7.6.3, and 8.0.0. The vulnerability stems from improper neutralization of script-related HTML tags within web pages served by FortiADC, enabling attackers to inject malicious scripts via specially crafted URLs. When a victim user interacts with such a URL, the injected script executes in the context of the victim's browser, potentially allowing unauthorized code execution or command execution within the web interface session. The attack vector is network-based (remote), with high attack complexity, requiring user interaction but no privileges or authentication. The vulnerability affects confidentiality and integrity by potentially exposing sensitive information or manipulating data through script execution, but does not impact system availability. The scope is changed (S:C), indicating that the vulnerability can affect resources beyond the initially vulnerable component. The CVSS 3.1 base score is 4.2 (medium severity), reflecting these factors. There are currently no known exploits in the wild, and no official patches have been linked yet. FortiADC is widely used for application delivery and load balancing, often deployed in enterprise and service provider environments to optimize and secure web traffic. The vulnerability could be leveraged in targeted phishing or social engineering campaigns to compromise administrative sessions or steal credentials. Given the nature of XSS, the risk is heightened if FortiADC interfaces are exposed to untrusted networks or users.

For European organizations, the impact of CVE-2025-58412 could be significant, particularly for those relying on FortiADC appliances for critical application delivery and load balancing functions. Successful exploitation could lead to unauthorized disclosure of sensitive information, session hijacking, or manipulation of web interface data, undermining confidentiality and integrity. This could facilitate further attacks such as credential theft, lateral movement, or disruption of security controls. Organizations in sectors such as finance, telecommunications, government, and critical infrastructure that deploy FortiADC are at elevated risk. The vulnerability's requirement for user interaction means phishing or social engineering could be used to lure victims into triggering the exploit. Although availability is not directly impacted, the compromise of administrative interfaces could indirectly affect service reliability. The absence of known exploits currently provides a window for proactive mitigation, but the medium severity rating and scope change indicate that the threat should not be underestimated.

To mitigate CVE-2025-58412, European organizations should immediately review and restrict access to FortiADC management interfaces, ensuring they are not exposed to untrusted networks or the public internet. Implement strict input validation and output encoding on all web interfaces to prevent script injection. Deploy and tune web application firewalls (WAFs) to detect and block malicious payloads targeting FortiADC URLs. Educate users and administrators about phishing risks and the importance of cautious interaction with unsolicited URLs. Monitor logs and network traffic for unusual or suspicious URL requests that may indicate attempted exploitation. Apply any forthcoming patches from Fortinet promptly once available. In the interim, consider disabling or limiting features that process user-supplied input in the FortiADC web interface if feasible. Conduct regular security assessments and penetration testing focused on web interface vulnerabilities. Employ multi-factor authentication (MFA) for administrative access to reduce the impact of potential credential compromise. Maintain an incident response plan tailored to web interface compromise scenarios.