The cypher may be prefectly impenetrable, but the software running on the transmitter or receiver may be more brittle. You cannot attack what you don't even know exists nearby.
A secure cipher is indistinguishable from random data, you can't infer what software is on either end just by eavesdropping.
You really need to look up the Kirchoff principle
A secure cipher is indistinguishable from random data, you can't infer what software is on either end just by eavesdropping.