Today Major Tom has released the pboot dumper if you remember the first time they showed us a dump of the PSVita memory card they use this pboot to retrieve it.
https://twitter.com/frtomtomdu80/status/673926642859950080
Now this pboot is not like the others but the process of installing is. Just use rejuvenate with Vitashell, VHBL, TN-V or Ark with Vita FTP to place the pboot.pbp into any psp game or demo. Then backup the game you place the pboot in then restore it and it will dump ux0 in ms0:temp after that use rejuvenate with Vitashell, VHBL, TN-V or Ark with Vitaftp to retrieve the dump in ms0: temp
You can follow our detailed tutorial here
Download: Pboot dumper