Exploited Zero-Day Flaw in Cisco UC Could Affect Millions

**Executive summary:** Cisco disclosed and patched CVE-2026-20045, a critical unauthenticated RCE in Unified Communications Manager and related products that can lead to root privileges; the vulnerability has been added to CISA’s Known Exploited Vulnerabilities catalog and Cisco reports attempted exploitation in the wild with signs of mass scanning for exposed management interfaces, so affected organizations should urgently apply fixes and mitigate exposed HTTP management access.