Cisco says hackers have been exploiting a critical bug to break into big customer networks since 2023

Cisco disclosed a critical CVSS 10.0 vulnerability in Catalyst SD‑WAN devices that is being actively exploited over the internet to obtain highest privileges and persistent hidden access; exploitation (tracked as UAT‑8616) has been observed since 2023, prompted multinational government alerts, and led CISA to order emergency patching because of risks to critical infrastructure and federal systems.