CVE-2025-20235: 
Cisco Secure Firewall Management Center vulnerability analysis and mitigation

CVE-2025-20235 is a cross-site scripting (XSS) vulnerability discovered in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software. The vulnerability was first disclosed on August 14, 2025, and affects multiple versions of Cisco Secure FMC Software. This security flaw allows an unauthenticated, remote attacker to conduct XSS attacks against users of the interface (Cisco Advisory).

The vulnerability stems from insufficient validation of user-supplied input by the web-based management interface. It has been assigned a CVSS v3.1 base score of 6.1 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. The vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation) (NVD).

A successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the interface or access sensitive, browser-based information. The vulnerability affects the confidentiality and integrity of the system, though it does not impact system availability (Cisco Advisory).

Cisco has released software updates that address this vulnerability. There are no workarounds available for this vulnerability. Customers are advised to regularly consult the advisories for Cisco products and ensure their devices have sufficient memory and compatible hardware configurations before upgrading (Cisco Advisory).