rsa-attack-techniques

Select and apply RSA cryptanalytic attacks from observed parameters and side-channel conditions.

2|Updated May 15, 2026
One-click install
npx skills add https://github.com/lNwNl/Methodos --skill rsa-attack-techniques
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: rsa-attack-techniques
Source: https://github.com/lNwNl/Methodos/tree/main/docker/opencode/skills/rsa-attack-techniques
Command: npx skills add https://github.com/lNwNl/Methodos --skill rsa-attack-techniques

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

It helps you recover RSA plaintext when you have RSA parameters (n, e, ciphertexts) and the system is vulnerable due to weak keys, small exponents, shared factors, or exploitable oracle/fault conditions.

Core Features & Use Cases

  • Attack Selection Playbook: Rapidly narrows down which RSA attack to attempt based on observable conditions (small n, small e, related messages, shared modulus factors, oracle access, or CRT faults).
  • Mathematics-Informed Cryptanalysis Guidance: Provides clear methods spanning factorization, small-exponent exploits, lattice techniques (Wiener/Boneh-Durfee/Coppersmith), broadcast/common modulus, and padding-oracle/fault attacks.
  • Detailed Implementations for Execution: Includes an “attack catalog” with mathematical derivations and implementation sketches (e.g., Pollard’s rho, Wiener full attack, RSA-CRT fault factoring, parity oracle, and Bleichenbacher flow).

Real-world use case

When you receive an RSA challenge where n is small enough to factor or where a padding/LSB oracle is observable, you can systematically identify the correct vulnerability class and apply the corresponding method to recover the message.

Quick Start

Load the skill and ask your AI: "Given n, e, and ciphertext c (plus any oracle outputs or fault evidence), which RSA attack should I run and what exact recovery steps should I follow?"

Frequently Asked Questions about rsa-attack-techniques

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I know which RSA attack to use when I have n, e, and a ciphertext?

RSA attack selection involves analyzing observable parameters like small n, small e, shared factors, or oracle access to route to the correct cryptanalytic method. This playbook matches your specific RSA conditions to the appropriate factorization, lattice, or oracle exploitation technique for plaintext recovery.

What RSA attacks can I use for small public exponents in a CTF challenge?

For small public exponents in RSA cryptanalysis, you can apply lattice-based small-root attacks like Coppersmith, or broadcast attacks if multiple ciphertexts are present. The skill provides mathematical derivations and implementation sketches for these small-exponent exploit techniques.

How do I recover RSA plaintext if I have access to a padding oracle?

Recovering RSA plaintext with a padding oracle involves exploiting the observable oracle responses to iteratively decrypt the message. This skill details the Bleichenbacher flow and parity oracle workflows to systematically extract plaintext from vulnerable RSA implementations.

Can I factor RSA moduli if multiple keys share common factors?

Yes, you can factor RSA moduli with shared factors using the common modulus technique or by computing the greatest common divisor across multiple keys. The attack catalog includes factorization methods like Pollard's rho to handle these shared modulus vulnerabilities.

Does this RSA cryptanalysis skill cover Wiener and Boneh-Durfee attacks?

Yes, this RSA cryptanalysis skill covers lattice techniques including the full Wiener attack and Boneh-Durfee method. These attacks target RSA vulnerabilities where the private exponent is small, providing mathematical derivations and implementation sketches for recovery.

How do I exploit RSA-CRT signature faults to recover a private key?

Exploiting RSA-CRT signature faults involves using the faulty signature output to factor the modulus and recover the private key. The skill provides an RSA-CRT fault factoring workflow that calculates the prime factors from the incorrect signature computation.