Advent of Cyber 2023 — Day 5

How large (in bytes) is the AC2023.BAK file?

• Open terminal in the machine
• type: dir & check the file size of AC2023.BAK

12,704

What is the name of the backup program?

• In the terminal, go to /TOOLS/BACKUP
• open the README.TXT file: edit README.TXT & check for program name

BackupMaster3000

What should the correct bytes be in the backup’s file signature to restore the backup properly?

this is from the README file

41 43

What is the flag after restoring the backup successfully?

• In terminal, type EDIT AC2023.BAK
• Change “X X” to “41 43”
• press ALT + F to save
• type C:\TOOLS\BACKUP\BUMASTER.EXE AC2023.BAK

THM{0LD_5CH00L_C00L_d00D}

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