CVE-2025-20265 is a critical remote code execution vulnerability affecting Cisco Secure Firewall Management Center (FMC) Software, specifically versions 7.0.7 and 7.7.0. The flaw resides in the RADIUS subsystem implementation used for authentication. During the authentication phase, the system improperly neutralizes special elements in user input, allowing an unauthenticated remote attacker to inject arbitrary shell commands. These commands are executed with high privileges on the device, potentially compromising the entire management center. Exploitation requires that the Cisco FMC is configured to use RADIUS authentication for either the web-based management interface, SSH management, or both. The vulnerability stems from insufficient input validation and sanitization of credentials sent to the RADIUS server, enabling injection attacks. The CVSS v3.1 base score is 10.0, reflecting the vulnerability's ease of exploitation (no authentication or user interaction required), complete confidentiality, integrity, and availability impact, and the potential for widespread compromise due to the critical role of FMC in network security management. Although no known exploits are currently reported in the wild, the severity and nature of the vulnerability make it a high-priority risk for organizations using affected Cisco FMC versions.

For European organizations, this vulnerability poses a severe risk to network security infrastructure. Cisco Firepower Management Center is widely used to manage firewall policies, intrusion prevention systems, and overall network security posture. Successful exploitation could allow attackers to gain full control over the FMC device, enabling them to alter firewall rules, disable security controls, exfiltrate sensitive data, or pivot deeper into the network. This could lead to significant data breaches, disruption of critical services, and loss of trust. Given the critical infrastructure and enterprise reliance on Cisco FMC, the impact extends to sectors such as finance, telecommunications, government, and critical infrastructure operators across Europe. The ability to execute arbitrary commands remotely without authentication increases the risk of automated attacks and rapid compromise. Additionally, the vulnerability's potential to affect confidentiality, integrity, and availability simultaneously makes it a threat to compliance with European data protection regulations such as GDPR, potentially resulting in legal and financial penalties.

1. Immediate upgrade to Cisco Secure FMC versions beyond 7.0.7 and 7.7.0 once patches are released by Cisco. Monitor Cisco’s official advisories for patch availability. 2. As a temporary mitigation, disable RADIUS authentication for the web-based management interface and SSH management if feasible, or restrict access to these interfaces via network segmentation and strict firewall rules limiting management access to trusted IP addresses only. 3. Implement multi-factor authentication (MFA) for management interfaces to add an additional layer of security, reducing the risk of unauthorized access even if the vulnerability is exploited. 4. Monitor network traffic and logs for anomalous authentication attempts or suspicious command execution patterns on FMC devices. 5. Employ intrusion detection/prevention systems to detect and block exploitation attempts targeting the RADIUS authentication process. 6. Conduct regular security audits and penetration testing focused on management infrastructure to identify and remediate similar injection vulnerabilities. 7. Educate network and security teams about the vulnerability and ensure incident response plans include scenarios involving FMC compromise.