“Originally Posted by graf_chokolo
I am able now to decrypt and decompress CORE_OS_PACKAGE.pkg from PS3 PUP-Files. The decrypted and decompressed package is a copy of FLASH region where all the important SELFs and isolated SPUs stored, e.g. lv1.self or isoldr.
So, now i could downgrade PS3 by writing this decrypted image to FLASH manually, without Update Manager from HV. In fact, Update Manager just do this But the problem is, that the SHA-1 hash values for these files are stored not in flash but in SC EEPROM and i don’t have access to it yet ”