Security researcher oct0xor has just released PS4 Registry Editor, a tool that lets you edit some registry files on the PS4.
For now, the tool lets you edit existing entries in the following files: system.dat, system.idx, system.eap, system.rec. Currently, the developer says, PS4 Registry Editor does not let you add new entries as it does not support rebuilding the registry. This might come later.
Additionally, the Security researcher has published a short writeup explaining some of the obfuscation used by Sony in their registry files.
Entries that the tool lets you tinker with include your PS4 nickname, your timezone and language; but also apparently more dangerous flags such as “idu_mode” and others. As always, keep in mind that messing up with your console’s registry could lead to a brick if you’re not careful, so proceed with care. (And in general, wait for people with the right set of skills to tell the scene what’s ok to modify or not).
Oct0xor adds that firmwares 5.01 and up are not supported yet, due to an additional layer of encryption.
Download PS4 Registry Editor
You’ll have to build the tool from source for now. The source code can be found on the developer’s github.