A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an authenticated, remote attacker to inject arbitrary HTML content into a device-generated document. This vulnerability is due to improper validation of user-supplied data. An attacker could exploit this vulnerability by submitting malicious content to an affected device and using the device to generate a document that contains sensitive information. A successful exploit could allow the attacker to alter the standard layout of the device-generated documents, read arbitrary files from the underlying operating system, and conduct server-side request forgery (SSRF) attacks. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Security Analyst (Read Only).