^{CVE-2023-20074:}Multiple stored XSS vulnerabilities in Cisco Firepower Management Center (FMC) Software allow unauthenticated remote attackers to execute arbitrary script code.

Overview

The Cisco Firepower Management Center (FMC) Software contains multiple stored cross-site scripting vulnerabilities (CWE-79) in its web-based management interface. These vulnerabilities occur because the application fails to properly validate user-supplied input before storing it and later displaying it to users. An unauthenticated remote attacker can exploit these vulnerabilities by inserting malicious script code into various data fields in the affected interface. When administrators or other users access the affected portions of the interface, the malicious code executes within their browser in the context of the FMC application. This could lead to cookie theft, credential harvesting, or other client-side attacks. Additionally, some exploits may cause temporary disruption to portions of the FMC Dashboard functionality.

Remediation

Organizations using affected versions of Cisco Firepower Management Center Software should:

1. Update to the latest software version as recommended in the Cisco Security Advisory (cisco-sa-fmc-xss-sK2gkfvJ).
2. Implement input validation and output encoding best practices for any custom applications that interact with the FMC.
3. Consider implementing Content Security Policy (CSP) headers if supported.
4. Limit access to the FMC web interface to trusted administrators and networks.
5. Monitor system logs for suspicious activities or attempted exploits.
6. Follow security best practices for web application security, including user training on recognizing phishing attempts that could leverage these vulnerabilities.

References

1. Cisco Security Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-sK2gkfvJ
2. CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'): https://cwe.mitre.org/data/definitions/79.html
3. OWASP XSS Prevention Cheat Sheet: https://cheatsheetseries.owasp.org/cheatsheets/Cross_Site_Scripting_Prevention_Cheat_Sheet.html