The disclosed computer-implemented method for detecting transactional message sequences that are obscured in multicast communications may include (i) collecting a sequence of messages that were distributed on a communication channel and that include an obscured cyclic sequence of request-response messages that are interleaved in the sequence of messages, (ii) constructing a sequence graph from the sequence of messages by (a) adding, for each unique message identifier in the sequence of messages, a node to represent the unique message identifier and (b) adding, for each unique sequence transition in the sequence of messages from an immediately-preceding message to an immediately-succeeding message, an edge to connect the nodes that represent the identifiers of the unique sequence transition's immediately-preceding and immediately-succeeding messages, (iii) traversing the sequence graph to discover the obscured cyclic sequence of request-response messages, and (iv) performing a security action. Various other methods, systems, and computer-readable media are also disclosed.