Author — Russian Substitution Cipher

Platform: CUSTOM | Category: Crypto | Type: Challenge | Difficulty: Medium | OS: N/A | **Author: XESXOR Techniques: russian_substitution_decryption, signature_analysis

Summary

Walkthrough of the CUSTOM Crypto Author — Russian Substitution Cipher. Task: Russian encrypted text with a signature asking to identify the author. Solution: Decrypt the substitution cipher signature to reveal REDACTED as the author.

Description

Russian encrypted text asking "Who is the author?" Signed "— Вдхеп Фибпдг"

Analysis

The text in Russian is encrypted with a substitution cipher. The signature at the end "— Вдхеп Фибпдг" is the encrypted author's name. We need to decrypt the signature and identify the author.

Analyzing the substitution pattern and using frequency analysis of the Russian language, we determine that the signature decrypts to "Томас Эдисон" (REDACTED).

Solution

 python read-only • copy allowed Copy
#!/usr/bin/env python3
# Signature: Вдхеп Фибпдг
# Decryption: Томас Эдисон
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# Substitution analysis:
# В → Т (shift by 18 positions in Russian alphabet)
# д → о
# х → м
# е → а
# п → с
# Ф → Э
# и → д
# б → и
# п → с
# д → о
# г → н

# This is a Vigenere-like cipher with Russian alphabet
# Flag is the author's name in English

author_russian = "Томас Эдисон"
author_english = "REDACTED"
print(f"Flag: {author_english}")

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Key Takeaways / Lessons

• Mastering russian_substitution_decryption, signature_analysis was key to this challenge.
• Always check for common misconfigurations and verify assumptions.

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Crafted by XESXOR Research • 2026-03-08 • CUSTOM • Author — Russian Substitution Cipher • Difficulty: Medium