Rate limiting is the most appropriate response because the attack specifically abuses the application ' s search functionality by generating excessive requests. Application-layer DoS attacks consume server-side resources through apparently legitimate HTTP requests rather than simply overwhelming network bandwidth. Applying rate limits to the affected search endpoint restricts how frequently individual clients or sessions can invoke the resource-intensive function, directly reducing the attack ' s effectiveness while allowing legitimate users to continue accessing the application. Moving to a higher-bandwidth host does not address exhaustion of application resources. Clearing the cache is unrelated to controlling malicious request volume. IP-based blocking can help in limited situations, but distributed attackers can rotate or spoof sources, making static blocking less effective. Rate limiting therefore provides targeted containment of the abused application functionality.

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