CISA orders feds to patch max-severity Cisco flaw by Sunday

CISA ordered federal agencies to urgently patch CVE-2026-20131 in Cisco Secure Firewall Management Center — a maximum-severity insecure-deserialization flaw allowing unauthenticated remote Java code execution as root — after Cisco confirmed no workaround and updated the advisory to report active exploitation. Amazon intelligence and vendor updates link the Interlock ransomware group to exploitation of this zero-day since January, and CISA added the CVE to its Known Exploited Vulnerabilities catalog and set an immediate remediation deadline for affected federal systems.