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**Identify by charset:**
- Base64: `A-Za-z0-9+/=`
- Base32: `A-Z2-7=` (no lowercase)
- Hex: `0-9a-fA-F`

See [encodings.md](encodings.md) for Caesar brute force, URL encoding, and full details.

import struct
floats = [1.234e5, -3.456e-7, ...]  # Whatever the challenge gives
flag = b''
for f in floats:
    flag += struct.pack('>f', f)
print(flag.decode())

import pandas as pd
import matplotlib.pyplot as plt

df = pd.read_csv('mouse_data.csv')

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file unknown_file
xxd unknown_file | head
binwalk unknown_file

7z x archive.7z           # Universal
tar -xzf archive.tar.gz   # Gzip
tar -xjf archive.tar.bz2  # Bzip2
tar -xJf archive.tar.xz   # XZ

while f=$(ls *.tar* *.gz *.bz2 *.xz *.zip *.7z 2>/dev/null|head -1) && [ -n "$f" ]; do
    7z x -y "$f" && rm "$f"
done

zbarimg qrcode.png       # Decode
qrencode -o out.png "data"

sox audio.wav -n spectrogram  # Visual data
qsstv                          # SSTV decoder

from pwn import *

r = remote('host', port)
r.recvuntil(b'prompt: ')
r.sendline(b'answer')
r.interactive()

for c in string.printable:
    result = test(f"{c}()")
    if "error" not in result.lower():
        print(f"Found: {c}()")

flag_len = int(test("L()"))
for i in range(flag_len):
    for c in range(32, 127):
        if query(i, c) == 0:
            flag += chr(c)
            break

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**Decorator bypass (ast.Call banned, no quotes, no `=`):**
```python

**String join bypass (`+` blocked):** `open(''.join(['fl','ag.txt'])).read()` -- see [pyjails.md](pyjails.md) for more.

from z3 import *

flag = [BitVec(f'f{i}', 8) for i in range(FLAG_LEN)]
s = Solver()
s.add(flag[0] == ord('f'))  # Known prefix

See [games-and-vms.md](games-and-vms.md) for YARA rules with Z3 and type systems as constraints.

import hlextend
sha = hlextend.new('sha256')
new_data = sha.extend(b'extension', b'original_message', len_secret, known_hash_hex)
new_hash = sha.hexdigest()

python pyinstxtractor.py packed.exe

See [games-and-vms.md](games-and-vms.md) for opcode remapping and marshal analysis.

import marshal, dis
with open('file.bin', 'rb') as f:
    code = marshal.load(f)
dis.dis(code)

PYTHONWARNINGS=ignore::antigravity.Foo::0
BROWSER="/bin/sh -c 'cat /flag' %s"

wasm2wat main.wasm -o main.wat

See [games-and-vms.md](games-and-vms.md) for full exploitation code and JS integration.

mult = 1000000000000000  # 10^15

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Initial: balance=5.00, inventory=0.00, flag_price=5.00, fee=0.05
Multiplier: 1e15 (time travel)

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def find_exploit(mult, balance_needed, inventory_needed):
    """Find x where selling int(x*mult) gives balance>=needed with inv>=needed"""
    for i in range(1, 500):
        x = i / 100.0
        if x >= 5.0:  # Can't buy more than balance
            break
        inv_after = x * mult
        bal_after = (5.0 - x) * mult

        # Sell integer part of inventory
        sell = int(inv_after)
        final_bal = bal_after + sell
        final_inv = inv_after - sell

        if final_bal >= balance_needed and final_inv >= inventory_needed:
            print(f'EXPLOIT: buy {x}, sell {sell}')
            print(f'  final_balance={final_bal}, final_inventory={final_inv}')
            return x
    return None

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See [games-and-vms.md](games-and-vms.md) for full attack chain and K8s privilege escalation checklist.

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grep -rn "flag{" .
strings file | grep -i flag
python3 -c "print(int('deadbeef', 16))"

import csv
with open('data.csv') as f:
    reader = csv.DictReader(f)
    flag = ''.join(chr(int(row['Times Borrowed'])) for row in reader)
print(flag)

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**Detection:** Characters appear invisible but have non-zero length. Check with `[hex(ord(c)) for c in text]` -- look for codepoints in `0xE0100-0xE01EF` or `0xFE00-0xFE0F` range.

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**Identification:** CJK characters, challenge mentions "translation" or "endian". See [encodings.md](encodings.md) for details.