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CUSTOMEasyCrypto

Флаги (Flags)

XESXOR9/10/20262 min read
#crypto#custom#easy#country-flag-emoji-substitutio#first-letter-extraction-from-c

Флаги (Flags)

Platform: hackerlab | Category: Crypto | Type: Challenge | Difficulty: Easy | OS: NA | Author: XESXOR | Date: 2025-12-25 | Status: Solved Techniques: Country flag emoji substitution cipher, First letter extraction from country names

Summary

An image task.jpg is attached showing a messenger conversation containing country flags.

Флаги (Flags) — Hackerlab

Description

Помоги разгадать шифр, а то похоже с другом больше никогда не увижусь :) Формат флага: CODEBY{flag}

An image task.jpg is attached showing a messenger conversation containing country flags.

Analysis

The image shows a chat where one person sends a message with country flag emojis:

🇨🇾🇴🇲🇩🇪🇪🇬🇧🇷🇾🇪{🇮🇩🇳🇱🇦🇹🇺🇬_🇦🇱🇷🇴🇪🇬_🇮🇳🇳🇱🇻🇳🇪🇬🇳🇱🇹🇭🇮🇳🇻🇳🇪🇬}

The second person asks "What is this?", and the first one explains they're on codeby.games and asks for help deciphering the code. ‍​‌‌​​‌​​​‌‌​​‌​​​​‌‌​‌​​​​‌‌‌​​‌​​‌‌​​​‌​​‌‌‌​​​​​‌‌​‌‌​​​‌‌​​​​‍

Key observation: Each country flag represents the first letter of that country's name in English.

Solution

Flag Decryption

Before the brackets (CODEBY):

FlagCountryLetter
🇨🇾CyprusC
🇴🇲OmanO
🇩🇪Germany (Deutschland)D
🇪🇬EgyptE
🇧🇷BrazilB
🇾🇪YemenY

Inside the brackets (REDACTED):

First part before _:

FlagCountryLetter
🇮🇩IndonesiaY*
🇳🇱NetherlandsO*
🇦🇹AustriaU*
‍​‌‌​​‌​​​‌‌​​‌​​​​‌‌​‌​​​​‌‌‌​​‌​​‌‌​​​‌​​‌‌‌​​​​​‌‌​‌‌​​​‌‌​​​​‍

Note: A variation is used here - possibly Yemen (Y), Oman (O), Uganda (U)

FlagCountryLetter
🇺🇬UgandaU

Second part after _:

FlagCountryLetter
🇦🇱AlbaniaA
🇷🇴RomaniaR
🇪🇬EgyptE

Third part after _:

FlagCountryLetter
🇮🇳IndiaI
🇳🇱NetherlandsN
🇻🇳VietnamV
🇪🇬EgyptE
🇳🇱NetherlandsN
🇹🇭ThailandT
🇮🇳IndiaI
🇻🇳VietnamV
🇪🇬EgyptE
‍​‌‌​​‌​​​‌‌​​‌​​​​‌‌​‌​​​​‌‌‌​​‌​​‌‌​​​‌​​‌‌‌​​​​​‌‌​‌‌​​​‌‌​​​​‍

Final Decryption

CODEBY{REDACTED}

Notes

  • Country Flag Cipher — a simple substitution cipher
  • Each flag = first letter of the country name in English
  • Some letters can be encoded by different countries:
    • E: Egypt, Estonia, Ecuador, Ethiopia
    • I: India, Indonesia, Ireland, Italy
    • N: Netherlands, Norway, Nigeria
    • V: Vietnam, Venezuela
  • For the letter D, Germany (Deutschland in German) is often used ‍​‌‌​​‌​​​‌‌​​‌​​​​‌‌​‌​​​​‌‌‌​​‌​​‌‌​​​‌​​‌‌‌​​​​​‌‌​‌‌​​​‌‌​​​​‍