Cisco confirms CVE-2026-20079 Secure FMC flaw exploited in attacks

CVE-2026-20079

September 9, 2026 · BleepingComputer · Severity: HIGH

This article reports that Cisco confirmed active exploitation of a critical authentication bypass vulnerability in Secure Firewall Management Center. The flaw allows unauthenticated attackers to gain administrative control, and Cisco has released patches urging immediate application. 📌 **Analyst Note:** This is a critical threat because Secure FMC is a central management point for firewall policies; a compromise could allow attackers to disable or reconfigure network defenses. Security teams should treat this as an emergency and verify patching across all instances.

Key Takeaways

Cisco has confirmed active exploitation of CVE-2026-20079, a maximum-severity authentication bypass vulnerability in Secure Firewall Management Center that allows unauthenticated remote attackers to gain full administrative control over affected devices.
Organizations using Cisco Secure FMC should immediately apply the patches released by Cisco, as the flaw requires no authentication and can lead to complete compromise of the firewall management infrastructure.
The vulnerability's CVSS score of 10.0 highlights the critical nature of this issue, and security teams must prioritize patching to prevent attackers from taking over network security appliances.