The target company's IP range is 151.113.0.0/16 and their border router's ASN (autonomous system numbers) includes their entire IP range. An attacker stands up their own border router with a unique AS

An ACK storm is a TCP-layer denial-of-service condition caused by forged ACK packets in a session, unrelated to BGP route announcements.

While BGP hijacking can cause a denial-of-service effect, the specific attack described - standing up a rogue ASN and advertising a stolen prefix - is definitionally BGP hijacking, not a generic DoS attack.

ARP cache poisoning is a Layer 2 attack that manipulates the ARP table on a local network segment; it has no relation to BGP or inter-domain routing.

BGP hijacking occurs when a malicious actor announces an IP prefix via BGP that they do not legitimately own, causing other autonomous systems to update their routing tables and forward traffic to the attacker's router. By advertising a more specific prefix (a /32 host route within the target's /16), the rogue route is preferred over the legitimate announcement due to BGP's longest-prefix-match rule, effectively intercepting or blackholing traffic destined for that IP.