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There are certainly methods to figure this out. It would help if there were a wealth of other files to compare it against. It would make sense that compression would come before encryption (as encrypted data is usually harder to compress.) Figuring out what type of compression algorithm is difficult...

Portions of the file are both compressed and encrypted. The compression of the file will make legitimate values in the ELF header to appear wrong (out of bounds.) If you look at the qword at 0x0018 you'll find what appears to be the file size before signing, compression, encryption, etc. This value ...