The present invention provides a method, system and program product for dynamically detecting an errant data sequence transmitted over a network and performing a corresponding action. Specifically, a data sequence is received by a server from a client and compared to a definable data structure. The data structure comprises rules that each correspond to a state of communication between the server and the client. Each rule sets forth a predetermined data sequence, an optional condition and an action. If the received data sequence: (1) matches one of the predetermined data sequences in the data structure; (2) is relevant to (was received during) the state of communication to which the matched predetermined data sequence corresponds; and (3) meets any enumerated conditions, a corresponding action is implemented.