Has anything like this been tried before with other spacecrafts?
You'd need to totally own the DSN. According to the Wiki:
Because of the enormous distances and the resultant weak signals from the spacecraft, the large antennas and the very sensitive receivers of the DSN are required to provide the necessary communications capabilities. The DSN is the world's largest and most sensitive spacecraft communications network. It consists of three deep space communications complexes located approximately 120 degrees of longitude apart around the world: at Goldstone, California; near Madrid, Spain; and near Canberra, Australia. This placement permits continuous communication with a spacecraft.
Perhaps listening to the traffic could help deciphering the encryption (if any). What it wouldn't be easy at all is to have antennae large enough and in various parts of the world: amateurs still don't have the capacity to do that.
> Has anything like this been tried before with other spacecrafts?
The only thing I can remember is reviving an old satellite with linux and SDR (https://www.ettus.com/blog/2014/07/contacting-a-36-year-old-...) but that was with some cooperation on part of NASAs.
“The best known of alleged takeovers of satellite control occurred in 2007 and 2008. In particular, a serious attack was observed in 2008 when hackers obtained the control of the NASA Terra EOS earth observation system satellite for 2 minutes in June and for another 9 minutes in October. Fortunately the attackers didn’t damage the satellite during the time they gained control of it.”
And then the 20kW+ transmitter you'd need...