The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added a critical deserialization vulnerability in Cisco Secure Firewall Management Center and Security Cloud Control to its Known Exploited Vulnerabilities catalog, citing evidence of active exploitation. Federal agencies are required to remediate the flaw by a mandated deadline under Binding Operational Directive 22-01, and CISA is urging all organizations to prioritize patching to prevent cyberattacks.