BMC · Baseboard Management Controller
An always-on chip that remotely monitors and manages a server's hardware independent of its CPU and OS.
Current numbers
CVSS 10.0CVE-2024-54085 AMI MegaRAC BMC auth-bypass via Redfish; added to CISA KEV 25 Jun 2025; OEM'd across 12+ server vendors
always-onBMC runs on standby power and boots before the host; a rooted BMC is an OS-invisible, persistent foothold under the CPU