Question and data repository for the 2024 Capture the Flag.
Server IP: 34.155.94.97
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 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?
12 | If the variable p
is set to (3 1 4 1 5 9)
, what does the command echo $((${p[0]} * ${p[2]}))
return?
13 | What is the grep
command flag used to select non-matching lines?
14 | What is the longer name of the -c
flag to grep
?
15 | How many lines are in file_a.txt
?
16 | What does the command head -n 10 file_a.txt | wc -l
return?
17 | How many words in file_a.txt
start with the letter "d"?
18 | How many words are in file_a.txt
that contain only 4 letters?
19 | What is the last word in file_b.txt
?
20 | What is the line number of the word "helicopter" in file_b.txt
?
21 | How many characters are in file_c.txt
?
22 | How many words contain "croissant" inside them in file_c.txt
?
23 | What word is at the same line in file_c.txt
as the word "sheep" is in file_a.txt
?
24 | What is the second word in file_c.txt
which contains the letter x
?
25 | What is the size of file_a.txt
in bytes?
26 | What is the command to display files in the current directory?
27 | What is the find command flag that limits the search to a certain depth in directories?
28 | What command would you use to display all currently running processes?
29 | What is the environment variable used to define the location of executable programs?
30 | What is the flag for diff that ignores case differences?
31 | What is the apt
command used to install available updates?
32 | 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?
33 | What is the file which lists locations that apt
fetches packages from?
34 | What is the name of the first column in top
by default?
35 | What is the letter of the command in top
to kill a process?
36 | What is the tmux
command to list all running sessions?
37 | What is the tmux
command to use an existing session?
38 | What is the letter of the tmux key binding to create a new window inside tmux
?
39 | What is the letter of the tmux key binding to leave the current client without stopping it?
40 | If you run tmux
on a remote server and then disconnect, will the tmux
session end? "yes" or "no"
41 | What is the name for the tutorial command to learn vim
?
42 | What is the name of the mode vim
starts in by default?
43 | What is the command to quit vim, without saving changes?
44 | What is the letter used to navigate up in vim
?
45 | What is the file used for a user's vim
configuration?
46 | What is the flag for the apt-get command to purge a package, including its configuration files?
47 | What is the apt command to update the list of available packages from sources listed in the sources list file?
48 | What is the linux command to check for available disk space?
49 | What is the letter of the command in htop to search for a specific process?
50 | What is the vim command to delete the current line?
51 | What is the vim command to yank (copy) the current line?
52 | What is the linux command used to display the IP addresses of all network interfaces?
53 | What key is used to scroll up one page in a man
page?
54 | After searching within a man
page, what key can be used to jump to the next occurrence of the search term?
55 | What key is used to jump to the beginning of a man
page?
56 | How many directories are there in the root directory of the machine-learning
repository?
57 | How many total files are there in the machine-learning
repository and all subdirectories? Not counting directories or hidden files like the .git
repository
58 | How many python or numpy files are in the machine-learning
repository and subdirectories?
59 | What is the short version of the commit ID of the first commit of the machine-learning
repository?
60 | What is the long version of the commit ID of the most recent commit of the machine-learning
repository?
61 | What city is mentioned in the 2nd most recent commit message of the machine-learning
repository?
62 | How many branches are in the machine-learning
repository? Don't double count references to the same branch.
63 | What is the name of the branch which isn't main
in the machine-learning
repository?
64 | How many different unique user addresses have pushed commits to the machine-learning
repository?
65 | What is the name of the LICENSE of the machine-learning
repository? Hint: it is also the full first line of the LICENSE file
66 | What is the git remote "origin" url of the seaborn repository?
67 | What is the full version of the last commit ID in the 0.12 version branch of seaborn?
The following questions concern the master
branch of seaborn at the commit 1e6739
.
68 | How many commits are in the master
branch of seaborn?
69 | How many tagged commits are there in the seaborn repository?
70 | How many "version" branches are there (ie, branches with a name starting in v)?
71 | What is the last item of the seaborn repository's gitignore?
72 | What is the first line of the setup.cfg
file in the seaborn repository?
73 | How many such key fields are in the setup.cfg
file in the seaborn repository?
74 | How many files are in the seaborn repository? Not counting hidden files like the .git
repository
75 | How many files directly contain the word "numpy" in the seaborn repository? Do not count hidden files like .git/
76 | What is the name of the Linux command used to generate SSH keys?
77 | What is the letter of the flag to specify the number of bits when generating an ssh key?
78 | What is the letter of the ssh
flag that denotes the private key to use for authentication?
79 | What is the letter of the ssh
flag to specify the user to log in as on the remote machine?
80 | What is the default port for ssh
?
81 | What is the first default private key file used by ssh
?
82 | What is the escape command to disconnect from an ssh
pseudoterminal?
83 | What is the standard location of the per-user SSH configuration file in Linux?
84 | What is the keyword to specify the private key file in an ssh configuration file?
The following questions pertain to the remote server:
85 | How many files (excluding directories) are there in ~/
?
86 | Where are the executables accessible to the user?
87 | How many binary executables are available to the user?
88 | What is the hostname of the server?
89 | What is the kernel name of the server?
90 | What is the release of the kernel of the server?
91 | What is the MAC address of the ethernet device of the server?
92 | What is the internal IP address of the server?
93 | What is the timezone of the server?
94 | What is the remote origin URL of the git repository at ~/repo/
?
95 | What is the name of the file (without the path) that has been removed in the git repository?
96 | How many lines are in the file ~/repo/data/dogc.txt
?
97 | What is the last line of the file ~/repo/data/muni-cat.txt
?
98 | How many times does the word "biblioteca" appear in all files in ~/repo/data/
?
99 | How many .txt
files are on the whole server?
100 | How many .txt
files are in the home directory or its subdirectories?
Questions 101 - 120 are the responses to the exercises in the Jupyter notebook python_intro.ipynb
, which is in the ctf2024
github repository. Some exercises can be solved by running the code in them; try to figure them out before running the code to get the solution.
121 | What is the type of a
in the code a = [None] * 4
?
122 | What is the character used to start a comment in Python?
123 | True or False: is
checks if the value of two variables are the same.
124 | True or False: ==
checks if the value of two variables are the same.
125 | What is the return value of the following code?
a = list(range(10))
b = a[:]
b is a
126 | What is the return value of the following code?
a = 'bonjour'
b = "bonjour"
a is b
127 | Which of math.ceil
and math.floor
gives the same result as round
for 0.5?
128 | What is the keyword used to start a function definition?
129 | What is the name of the function used to remove whitespace in a python string?
130 | What is the type of the following code: ["a", "b", "c"]
?
131 | What is the type of the following code: {"a", "b", "c"}
?
132 | What is the type of the following code: "a", "b", "c"
?
133 | How many times does the following code print?
for i in range(10):
if i == 4:
break
print(i)
134 | How many times does the following code print?
for i in range(10):
if i == 4:
continue
print(i)
135 | How many times does the following code print?
for i in range(10):
if i == 4:
pass
print(i)
136 | How many times does the following code print?
for n in range(2, 10):
for x in range(2, n):
if n % x == 0:
break
else:
print(n)
137 | What does http_error(402)
return in the following code?
def http_error(status):
match status:
case 400 | 401 | 403 | 404:
return "Bad request"
case 418:
return "I'm a teapot"
case _:
return "Something is wrong with the internet"
138 | What does the following code print?
def foo(arg, /):
print(arg)
try:
foo(arg=3)
except:
print(4)
139 | What does the following code print?
def foo(*, arg):
print(arg)
try:
foo(4)
except:
print(3)
140 | What does the following code print?
def foo(a, /, b, *, c):
print(a, b, c)
try:
foo(1, b=2, c=3)
except:
print(3, 4, 5)
141 | What is the return value of the following code?
from datetime import timedelta
a = timedelta(weeks=2, hours=3, seconds=32)
b = timedelta(hours=3, seconds=32, days=14, weeks=0)
a == b
142 | What is the first argument to the datetime.date
function?
143 | What is the return value of the following code?
import time
from datetime import date
date.today() == date.fromtimestamp(time.time())
144 | What is the directive used for a month's full name in strftime
?
145 | What is the second to last element of a datetime timetuple
?
146 | What is the result of math.fsum([0.1]*10)
?
147 | What is the result of sum
on the same list?
148 | What is the result of math.isclose(math.fsum([0.1]*10), sum([0.1]*10))
?
149 | What is the python math
function to check if a value is not a number?
150 | What is the return value of the code math.log(1234, 10) == math.log10(1234)
?
151 | What is the return value of math.pow(3, 0)
?
152 | What is the name of the python standard library that contains the functions mean
, median
, and mode
?
153 | What is the name of the pickle
function to write a pickled version of an object to a file?
154 | True or False: all classes that are defined inside a module can be pickled.
155 | What does the following code print?
print(json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True))
156 | What is the expected type of the first argument of json.loads
?
157 | What does the value "null" in JSON correspond to in Python?
158 | What is the return of the following code?
json.loads('{"x": 1, "x": 2, "x": 3}')
159 | What is the function name in the requests
package to make an HTTP POST request?
160 | What is the name of the argument for providing an HTML payload in an HTTP POST request in the requests
library?
Questions 161 - 200 are in the numpy and pandas notebooks.
161 - 180 | numpy.ipynb
181 - 195 | pandas_titanic.ipynb
196 - 200 | pandas_air_quality.ipynb