In the cyber kill chain methodology, the phase where Jame is creating a tailored malicious deliverable that includes an exploit and a backdoor is known as 'Weaponization'. During this phase, the attacker prepares by coupling a payload, such as a virus or worm, with an exploit into a deliverable format, intending to compromise the target's system. This step follows the initial 'Reconnaissance' phase, where the attacker gathers information on the target, and precedes the 'Delivery' phase, where the weaponized bundle is transmitted to the target. Weaponization involves the preparation of the malware to exploit the identified vulnerabilities in the target system.References:

Lockheed Martin's Cyber Kill Chain framework

"Intelligence-Driven Computer Network Defense Informed by Analysis of Adversary Campaigns and Intrusion Kill Chains," leading to the development of the Cyber Kill Chain framework