this-is-NOT-the-flag

this-is-NOT-the-flag/NOTflag.txt

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+nZyenIuZhMiXtoygzoygyJfMoJmTnsaC

this-is-NOT-the-flag/chall.yaml

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+name: This is NOT the flag
+categories:
+  - misc
+value: 50
+flag:
+  file: ./flag.txt
+description: |
+  The flag is NOT inside this file. Do NOT even bother checking.
+hints: 
+  - The flag is ASCII encoded in base 64
+authors:
+  - Jacob Korn
+files:
+  - src: ./NOTflag.txt
+visible: true

this-is-NOT-the-flag/flag.txt

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+bcactf{7hIs_1s_7h3_fla9}

this-is-NOT-the-flag/solve.py

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+from base64 import b64decode
+
+with open('NOTflag.txt', 'r') as f:
+    data = b64decode(f.read())
+    s=''
+    for byte in data:
+        s+=chr(byte ^ 0xFF) # NOT all 8 bits
+    print(s)
+

this-is-NOT-the-flag/solvepath.txt

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+1. turn string into binary (ascii)
+2. NOT it
+3. turn binary into string