Question and data repository for the 2023 Capture the Flag.

1 | Where is the curl executable located? Some systems vary, if your answer is incorrect, try a common alternative.

2 | What is the linux command used for reading manuals?

3 | Where is the less executable located?

4 | What is the key for scrolling down by one half of screen size in less?

5 | What is the longer name of the -K flag to curl?

6 | What is the cp command flag allowing for copying directories?

7 | What is the ls command flag used for human-readable output?

8 | What is the mv command flag which will interactively prompt before overwriting files?

9 | What is the cat command flag which shows line numbers?

10 | If the variable STRING is set to banana, what does the command echo ${STRING:4}$ return?

11 | If the variable STRING is set to to be or not to be, what does the command echo ${STRING[@]/be/eat} return?

12 | If the variable a is set to 3 and b is set to 4, what does the command if [[ $a -le $b ]]; then echo $a; else echo $b; fi return?

13 | If the variable p is set to (3 1 4 1 5 9), what does the command echo $((${p[0]} * ${p[2]})) return?

14 | What is the grep command flag used to select non-matching lines?

15 | What is the longer name of the -c flag to grep?

16 | How many lines are in file_a.txt?

17 | What does the command head -n 10 file_a.txt | wc -l return?

18 | How many words in file_a.txt start with the letter "d"?

19 | How many words are in file_a.txt that contain only 4 letters?

20 | What is the last word in file_b.txt?

21 | How many words contain "ello" inside them in file_b.txt?

22 | What is the line number of the word "helicopter" in file_b.txt?

23 | What is the line number of the word "croissant" in file_c.txt?

24 | How many characters are in file_c.txt?

25 | How many words contain "croissant" inside them in file_c.txt?

26 | How many words end with the letter "t" in file_c.txt?

27 | How many words start with the letter "c" in file_c.txt?

28 | How many words have the letter "o" directly followed by either "u" or another "o" in file_c.txt?

29 | What word is at the same line in file_c.txt as the word "sheep" is in file_a.txt?

30 | What is the second word in file_c.txt which contains the letter x?

31 | How many directories are there in the root directory of the machine-learning repository?

32 | How many total files are there in the machine-learning repository and all subdirectories? Not counting directories or hidden files like the .git repository

33 | How many python or numpy files are in the machine-learning repository and subdirectories?

34 | What is the short version of the commit ID of the first commit of the machine-learning repository?

35 | What is the long version of the commit ID of the most recent commit of the machine-learning repository?

36 | What is the most recent commit message of the machine-learning repository?

37 | How many branches are in the machine-learning repository? Don't double count references to the same branch.

38 | What is the name of the branch which isn't main in the machine-learning repository?

39 | How many different unique user addresses have pushed commits to the machine-learning repository?

40 | What is the name of the LICENSE of the machine-learning repository? Hint: it is also the full first line of the LICENSE file

41 | What is the git remote "origin" url of the seaborn repository?

42 | What is the full version of the last commit ID in the 0.12 version branch of seaborn?

43 | How many commits are in the master branch of seaborn?

44 | How many tagged commits are there in the seaborn repository?

45 | How many "version" branches are there (ie, branches with a name starting in v)?

The following questions concern the master branch of seaborn.

46 | What is the last item of the seaborn repository's gitignore?

47 | What is the first line of the setup.cfg file in the seaborn repository?

48 | How many such key fields are in the setup.cfg file in the seaborn repository?

49 | How many files are in the seaborn repository? Not counting hidden files like the .git repository

50 | How many files directly contain the word "numpy" in the seaborn repository? Do not count hidden files like .git/

51 | What is the name of the linux command used to generate SSH keys?

52 | What is the letter of the flag to specify the number of bits when generating an ssh key?

53 | What is the letter of the ssh flag that denotes the private key to use for authentification?

54 | What is the letter of the ssh flag to specify the user to log in as on the remote machine?

55 | What is the default port for ssh?

56 | What is the first default private key file used by ssh?

57 | What is the escape command to disconnect from an ssh pseudoterminal?

58 | What is the standard location of the per-user ssh configuation file in Linux?

59 | What is the keyword to specify the private key file in an ssh configuration file?

The following questions pertain to the remote server.

60 | How many files (excluding directories) are there in ~/?

61 | What are the directories with binary executables accessible to the user (ie PATH)?

62 | How many binary executables are available to the user?

63 | What is the hostname of the server?

64 | What is the kernel name of the server?

65 | What is the release of the kernel of the server?

66 | What is the MAC address of the ethernet device of the server?

67 | What is the internal IP address of the server?

68 | What is the timezone of the server?

69 | What is the remote origin url of the git repository at ~/repo/?

70 | What is the name of the file (without the path) that has been removed in the git repository?

71 | How many lines are in the file ~/repo/data/dogc.txt?

72 | What is the last line of the file ~/repo/data/muni-cat.txt?

73 | How many times does the word "biblioteca" appear in all files in ~/repo/data/?

74 | How many .txt files are on the whole server?

75 | How many .txt files are in the home directory or its subdirectories?

76 | What is the apt command used to install available updates?

77 | What is the letter of the apt-get command flag to perform a test run of the installation that does not actually change the system?

78 | What is the file which lists locations that apt fetches packages from?

79 | What is the name of the first column in top by default?

80 | What is the letter of the command in top to kill a process?

81 | What is the tmux command to list all running sessions?

82 | What is the tmux command to use an existing session?

83 | What is the letter of the tmux key binding to create a new window inside tmux?

84 | What is the letter of the tmux key binding to leave the current client without stopping it?

85 | If you run tmux on a remote server and then disconnect, will the tmux session end? "yes" or "no"

86 | What is the name for the tutorial command to learn vim?

87 | What is the name of the mode vim starts in by default?

88 | What is the command to quit vim, without saving changes?

89 | What is the letter used to navigate up in vim?

90 | What is the file used for a user's vim configuration?