47w ago - Following up on his PSN / SEN Enabler and Disabler v4.31, PlayStation 3 homebrew developer Nathan_r32_69 (aka nathanr3269) has released a PS3 PUP's Syscon Changer v1.0 followed by v1.1 and v1.2 for those interested with details below.
To quote: Hi friends, i'm here again with a new tool to make it easy another task, this time to change PUP's syscon, for for example, install a lower PUP on higher firmware, like Downgrader PUPs does
USE IT WITH CAUTION - ONLY FOR CFW FOR NOW
Its to easy to use, only chose your PUP file, select syscon version and click on "Start", if all goes fine you will have a new file named "NEW-PS3UPDAT.PUP"
Hope you will find this tool useful and contact me if you see any issue, meanwhile i'll back to finish SEN Enabler v5.0 and other research
Finally, from Cyberskunk: Basicly this changes the firmware version in the info0 of the CORE_OS_PACKAGE.pkg so the PS3 thinks you are installing a higher CoreOS.. Same way the '999' Downgrader works.. And NO.. It will never downgrade 3.56+ OFW.. Ever!!
To do do this you would need to exploit the OFW and try to stop it from checking the spkg_hdr.1 files or return success (if you had an exploit like this you could do a hell of a lot more than just installing firmware)
OR Some disgruntled employee at Sony would need to leak the private key for spkg_hdr.1 files. This private key can no longer be calc'd and it is not, never has been nor will ever be in the firmware. Sorry to burst any bubbles of people thinking it will happen sometime soon..
New version v1.1 released: PUP file must be where you unpack the program
Fixed some issues while unpackin Core_OS and creating spkg files, must work fine now
Fixed all previous bugs
Added executable to install the variable of the keys
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