CVE-2025-20293 is a vulnerability identified in Cisco IOS XE Software specifically affecting the Catalyst 9800 Series Wireless Controllers for Cloud (9800-CL). The flaw arises from incomplete cleanup during the Day One setup process of the device. This incomplete cleanup leaves the public-key infrastructure (PKI) server accessible to unauthenticated remote attackers. Exploitation is possible by sending crafted Simple Certificate Enrollment Protocol (SCEP) requests to the affected device. Successful exploitation allows an attacker to request and obtain a certificate from the virtual wireless controller. With this certificate, the attacker can then authenticate an attacker-controlled device to the wireless controller, effectively joining the network as a trusted device. The vulnerability affects a broad range of IOS XE versions from 16.10.1 through various 17.x releases, indicating a wide exposure across many deployed devices. The CVSS v3.1 score is 5.3 (medium severity), reflecting that the attack vector is network-based, requires no privileges or user interaction, and impacts confidentiality but not integrity or availability. No known exploits are reported in the wild as of the publication date. The root cause is the failure to properly remove or disable the PKI server interface after initial setup, which should normally restrict certificate enrollment to authorized entities only. This vulnerability could be leveraged to bypass network access controls by issuing valid certificates to unauthorized devices, potentially leading to unauthorized network access and lateral movement within enterprise environments relying on these wireless controllers for secure connectivity.

For European organizations, this vulnerability poses a significant risk to the security of wireless network infrastructure, especially in sectors heavily reliant on secure wireless communication such as finance, healthcare, government, and critical infrastructure. Unauthorized devices gaining access to corporate wireless networks can lead to data exfiltration, espionage, or serve as a foothold for further attacks within the internal network. Given the widespread deployment of Cisco Catalyst 9800 Series controllers in enterprise and service provider environments across Europe, exploitation could undermine trust in wireless network authentication mechanisms. The ability to obtain valid certificates without authentication compromises the confidentiality of network access controls and could facilitate man-in-the-middle attacks or unauthorized access to sensitive systems. Although the vulnerability does not directly impact system integrity or availability, the indirect consequences of unauthorized network access could be severe, including regulatory non-compliance under GDPR if personal data is exposed. The medium CVSS score reflects the need for timely remediation to prevent potential exploitation, especially as no user interaction or privileges are required for an attacker to exploit this remotely.

1. Immediate deployment of Cisco-released patches or software updates that address this vulnerability is the most effective mitigation. Organizations should prioritize upgrading affected IOS XE versions to fixed releases as soon as they become available. 2. Until patches are applied, restrict network access to the management interfaces of Catalyst 9800-CL controllers using network segmentation and access control lists (ACLs) to limit exposure to trusted administrative hosts only. 3. Monitor network traffic for unusual SCEP requests or certificate enrollment activity that could indicate exploitation attempts. Implement logging and alerting on certificate issuance events. 4. Review and harden the Day One setup process configurations to ensure that PKI servers are properly disabled or cleaned up post-setup. 5. Employ network access control (NAC) solutions that can detect and block unauthorized devices even if they possess valid certificates. 6. Conduct regular audits of issued certificates and revoke any that appear suspicious or unauthorized. 7. Educate network administrators on the risks of incomplete setup processes and the importance of following Cisco’s security best practices for wireless controller deployment.