![image](https://github.com/jeromepalayoor/ctf-archive-hub/assets/63996033/5820117f-ad55-426b-addb-02486290ebd9)
Error in data.txt as it is not a multiple of 3:
```IIqrBRz → IqrBrzS4mLtKOIqr2stRbcQHJAPR2svphjHu0 → 4mLtKOIqr2stRbcQHJAPR2svphjHu0```
Looks like a substitution cipher but each letter is represented by a random group of 3 characters. So, just assign each group of 3 into a letter and use [quipqiup](https://quipqiup.com/).
```pyg = ""bad = ",.\n {}"with open("data.txt", "r") as f:    for c in f.read():        if c not in bad:            g += c
abc = [chr(i) for i in range(97, 123)]g = [g[i:i+3] for i in range(0, len(g), 3)]# split into groups of 3found = []s = ""i = 0for k in g:    if k not in found:        found.append(k)        s += abc[i]        i += 1    else:        d = found.index(k)        s += abc[d]# assign 1 letter for each groupprint(s)
>>> "abcdebefgchijhekclijmjbnechehoplfieqremmcdesakethjksimbchducdesmijashqcqsaaepehifbcshievijaigemcrebchducdebjhdehjudgijasbbjhemgeeijpmjchqigehkeojuhiigejoouppehoemjaecogbeiiepimsbbedcbijjkhwumijhedushecfsdshksixepbchq"```
![image](https://github.com/jeromepalayoor/ctf-archive-hub/assets/63996033/64abcd78-ab2c-498a-a821-4019b2d22265)
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