Critical active threat
CVE-2026-20131 Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of Untrusted Data
- Actively exploited (CISA KEV)
- Listed on CISA KEV
- Network edge / SD-WAN deployments affected
Cisco Secure Firewall Management Center (FMC) Deserialization is on CISA KEV — confirmed in-the-wild exploitation. Expect continued targeting while the issue remains on the catalog.