Internet-Security.com UDP port 68 details

UDP port 68 is the DHCP/BOOTP client port used by devices to receive configuration from DHCP servers (which send from UDP 67).
Microsoft Windows (including Windows Server) uses the DHCP Client service on UDP 68 to obtain IP settings.
Linux systems use DHCP clients such as ISC dhclient, systemd-networkd’s DHCP client, NetworkManager, dhcpcd, or BusyBox udhcpc on UDP 68.
Apple macOS and iOS use the built-in DHCP client (via configd) listening on UDP 68 for address assignment.
Android uses its built-in DHCP client (e.g., dhcpcd in some versions) on UDP 68 when joining networks.
Network gear like Cisco IOS/IOS-XE and Juniper Junos devices, plus Ubiquiti UniFi access points, use UDP 68 on interfaces configured as DHCP clients.
Virtualization and cloud environments (VMware ESXi hosts and guest VMs, KVM/Libvirt guests, Hyper-V guests, common cloud images) acquire addresses via DHCP clients on UDP 68.
IP phones and printers (e.g., Poly/Yealink phones, HP printers) use UDP 68 to obtain network settings.
PXE network boot clients use UDP 68 to receive BOOTP/DHCP offers and boot parameters.
Security note: UDP 68 traffic can be abused by rogue DHCP servers and crafted replies; client-side flaws (e.g., ISC dhclient CVE-2018-1111) have enabled code execution via malicious DHCP responses.

UDP 68