Icarus Online (Riders of Icarus) .pak extract file

[BOMDEBOLA]

Hey guys, how are you? I hope you're well, is it here that people have their minds unlocked in the matrix? 😆

Jokes aside, I'm trying to extract some files from this game: https://www.icarusonline.co.kr/main , and an old game made in CryEngine 3.

the file format is .pak or .npk, an old program called PakDecrypt was able to extract files from it just using the RSA Key, but in 2024 the encryption method was changed and since then it is no longer possible to extract files.

I would like to know if anyone would be able to figure out what obfuscation method was inserted into the game, you can say below how far I got, but I lack the skills to go further.

This is the old .npk package: https://www.mediafire.com/file/xe4vvm3mxfhvawo/oldPakdecrypt.rar/file

This is the new .npk package, it cannot be extracted like the old one.: https://www.mediafire.com/file/3toy0lwn21ledms/newsounds0.npk/file

the RSA key has not changed,  I think they included something else besides the RSA key

The additional encryption appears to be in either Cry Game.dll or Cry System.dll

an initial analysis of the same file after May 2024, which was when they changed the encryption, may provide us with clues

I found this function using ghidra

twofish ? So besides RSA a new key? I don't know

this is the old bin64: https://www.mediafire.com/file/ivuywx5in21apyo/oldBin64.rar/file

this is the new bin64: https://www.mediafire.com/file/563qvap1w6dqdxi/Bin64.zip/file