Adds CTFs to content

Add CTFs from 2024 to the content, htb apocalypse, spookyCTF,
buckeye ctf and some edits to the 404 ctf

content/writeups/2024/htb_apocalypse/_index.md

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+date = '2024-06-22T15:41:13+02:00'
+draft = false 
+title = 'HTB apocalypse'
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+
+Two challenges solved for this ctf

content/writeups/2024/htb_apocalypse/misc/StopDropAndRoll.md

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+date = '2024-06-22T15:41:13+02:00'
+draft = false 
+title = 'Stop drop and roll'
+tags = [ 'misc' ]
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+
+A simple misc challenge which involves using a TCP connection to play a simple game in which you have to answer to a request with specific words.
+
+For exemple : `GORGE FIRE PHREAK` must be answered to by `STOP-ROLL-DROP`
+
+To do so I wrote a simple python script :
+```python
+import socket
+import time
+
+def main():
+    # Connect to the server
+    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    s.connect(("83.136.249.153", 30914))
+    s.recv(4096).decode()
+    s.sendall(b"y\n") # We must send 'y' to start the game
+    message = s.recv(1024).decode()[19:] # We receive the data
+    print(message)
+    while True:
+        response = create_response(handle_input(message)) # And we answer
+        print(response)
+        time.sleep(0.5)
+        s.sendall(response.encode())
+        time.sleep(0.5)
+        message = s.recv(4096).decode() # And we start again
+        print(message)
+
+
+def create_response(input:list) -> str:
+    back = str()
+    for mon in input:
+        # Add the correct word
+        if mon == "GORGE":
+            back += "STOP"
+        elif mon == "FIRE":
+            back += "ROLL"
+        elif mon == "PHREAK":
+            back += "DROP"
+        back += "-"
+    back = back[:-1] # Remove the last '-'
+    back += "\n"
+    return back
+
+def handle_input(input:str) -> list:
+    # Transform the data into a list to make it easier to handle
+    data_raw = str()
+    for c in input:
+        data_raw += c
+        if c == "\n": break
+    data = list()
+    word = str()
+    for c in data_raw:
+        if c != "," and c != " " and c != "\n":
+            word += c
+        elif c == ",":
+            data.append(word)
+            word = ""
+    data.append(word)
+    return data
+
+
+if __name__ == "__main__":
+    main()
+```

content/writeups/2024/htb_apocalypse/misc/unbreakable.md

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+date = '2024-06-22T15:41:13+02:00'
+draft = false 
+title = 'Unbreakable'
+tags = [ 'misc' ]
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+
+The goal of this challenge is to bypass the following python script to print a file to the screen.   
+We notice a blacklist which stops us from using quite a lot of characters.   
+Using open to get the content of the file and printing it is no problem : `print(open('flag.txt','r').read())`   
+The problem are the parenthesis in the eval which creates an error when trying to execute our command. `eval(ans + '()')`   
+I first tried to use str and use one of the str methods to convert the None returned by print to a string and avoid throwing an exception.  
+But it wasn't working so i found that it is possible to call multiple functions on one line by separating them with a comma.   
+So the final payload is : `print(open('flag.txt','r').read()),print`
+
+
+```python
+#!/usr/bin/python3
+
+banner1 = 'Coucou'
+
+banner2 = 'EZ'
+
+blacklist = [ ';', '"', 'os', '_', '\\', '/', '`',
+              ' ', '-', '!', '[', ']', '*', 'import',
+              'eval', 'banner', 'echo', 'cat', '%', 
+              '&', '>', '<', '+', '1', '2', '3', '4',
+              '5', '6', '7', '8', '9', '0', 'b', 's', 
+              'lower', 'upper', 'system', '}', '{' ]
+
+while True:
+  ans = input('Break me, shake me!\n\n$ ').strip()
+  
+  if any(char in ans for char in blacklist):
+    print(f'\n{banner1}\nNaughty naughty..\n')
+  else:
+    try:
+      eval(ans + '()')
+      print('WHAT WAS THAT?!\n')
+    except:
+      print(f"\n{banner2}\nI'm UNBREAKABLE!\n") 
+```