Explanation:
The SolarWinds attack, also known as the Sunburst attack, was a supply chain attack where attackers inserted malicious code into the company's Orion software updates. This update was then distributed to thousands of SolarWinds' customers, including government agencies and large corporations. The attack allowed hackers to gain access to sensitive networks and systems.
Inserting hostile code into the software update is the specific method used in this attack.
The attack was not a DDoS attack or involved crashing servers, but rather a stealthy infiltration via trusted updates.
Thus, the primary technique was compromising the software update process to spread malicious code.