rsa-attack-techniques

rsa-attack-techniques is a skill for Claude Code, Codex from JustineDevs/premortem. It costs 53 tokens per session (3,694 once invoked), scanned A, a copy of rsa-attack-techniques, Apache-2.0.

A security testing guide for finding weaknesses in RSA, a public-key encryption system, when its keys or padding are used incorrectly.

In plain words
What is it for?
It is for authorized security assessments and capture-the-flag challenges involving RSA parameters, weak keys, small exponents, shared factors, or padding oracles.
Why use it?
It helps choose an attack that matches the RSA values available, instead of trying unrelated cryptanalysis methods.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit It is for authorized security assessments and capture-the-flag challenges involving RSA parameters…

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/justinedevs/premortem/rsa-attack-techniques
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add JustineDevs/premortem --skill rsa-attack-techniques
Clone the repo
git clone --depth 1 https://github.com/JustineDevs/premortem

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for rsa-attack-techniques

README.md
[![agentmods](https://agentmods.dev/badge/skills/justinedevs/premortem/rsa-attack-techniques.svg)](https://agentmods.dev/skills/justinedevs/premortem/rsa-attack-techniques)
Your own site
<a href="https://agentmods.dev/skills/justinedevs/premortem/rsa-attack-techniques"><img src="https://agentmods.dev/badge/skills/justinedevs/premortem/rsa-attack-techniques.svg" alt="Measured on agentmods" height="20"></a>
Per session 53 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,694 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00053 $0.03694
Opus 5 $0.00026 $0.01847
Sonnet 5 $0.00011 $0.00739
Haiku 4.5 $0.00005 $0.00369

Measured 3d ago against content hash 33917f91cf9a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

rsa-attack-techniques scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to rsa-attack-techniques — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/rsa-attack-techniques/SKILL.md · 438 lines

How it starts

The opening of the file, as written. The whole thing — 438 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SKILL: RSA Attack Techniques — Expert Cryptanalysis Playbook

AI LOAD INSTRUCTION: Expert RSA attack techniques for CTF and authorized security assessments. Covers factorization attacks, small exponent exploits, lattice-based approaches (Wiener/Boneh-Durfee/Coppersmith), broadcast attacks, common modulus, padding oracles, and fault attacks. Base models often suggest attacks that don't match the given parameters or miss the correct attack selection based on what's known.

Advanced Reference

Also load RSA_ATTACK_CATALOG.md when you need:

  • Detailed SageMath/Python implementation for each attack
  • Step-by-step mathematical derivation
  • Edge cases and failure conditions per attack

Quick attack selection

Given / Observable Attack Tool
Small n (< 512 bits) Direct factorization factordb, yafu, msieve
e = 3, small message Cube root gmpy2.iroot
Multiple (n, c) same small e Hastad broadcast CRT + iroot
Very large e or very small d Wiener / Boneh-Durfee SageMath, RsaCtfTool
Partial p knowledge Coppersmith small roots SageMath
Same n, different e Common modulus Extended GCD
Multiple n values Batch GCD (shared factor) Python/SageMath
Padding error oracle Bleichenbacher Custom script
LSB parity oracle LSB oracle attack Custom script
Fault in CRT computation RSA-CRT fault Single faulty signature

1. FACTORIZATION ATTACKS

1.1 Direct Factorization (Small n)

from sympy import factorint

n = 0x...  # small modulus
factors = factorint(n)
p, q = list(factors.keys())

Read the full file on GitHub · 438 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 438 lines · 53 tokens per session scan A 33917f91cf9a

Subscribe to this mod's changes

rsa-attack-techniques is a skill published in the GitHub repository JustineDevs/premortem (2 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 53 tokens to every session and 3,694 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to rsa-attack-techniques, differing in 0 lines, and is treated as a copy.

Related

Other skills, from other repositories

awesome-azd-template-submit

Submit an azd template to the awesome-azd gallery. Use when asked to submit, add, or contribute a template to awesome-azd. Requires only a GitHub repository URL — all metadata (title, description, languages, frameworks, Azure services, IaC) is auto-detected by the submission pipeline.

Azure/awesome-azd · 72 tokens

bitbottle

Reference for the bitbottle CLI — a gh-style tool for Bitbucket Server/DC and Cloud. Load when the user asks about bitbottle commands, auth setup, PRs, repos, branches, tags, commits, pipelines, or why a command failed. Load even if the user just says "bitbottle", mentions "Bitbucket", or pastes a bitbottle error…

proggarapsody/bitbottle · 84 tokens

azure-cli

Operational skill for agents to manage Microsoft Azure via az CLI - subscriptions, resource groups, AKS, App Service, Key Vault, and RBAC hygiene.

alivirgo/Major-AI-Skills · 34 tokens

azure-cli

A command-line tool for managing Microsoft Azure, Microsoft's cloud platform, from a terminal. It covers account sign-in, subscriptions, resource groups, virtual machines, and other cloud resources.

chaterm/terminal-skills · 7 tokens

extract-api

This skill should be used when the user asks to "extract API from", "import API from", "add commands from this repo", "register API from docs", "convert docs to CLI commands", "import Postman collection", or provides a GitHub repository URL, a documentation site URL, a Postman collection file/URL, or a local API…

hesedcasa/sdkck · 86 tokens

sidekick

ALWAYS run sdkck search FIRST before using ANY tool, MCP server, Bash command, or external API. sdkck is the canonical command surface for Jira, Sentry, MySQL, Postgres, Supabase, Bitbucket, Confluence, and imported OpenAPI/Postman specs. Trigger on every task involving external systems, APIs, databases, tickets…

hesedcasa/sdkck · 100 tokens