ctf-web

A collection of web-application attack techniques for capture-the-flag (CTF) security challenges. Web applications are software reached through a browser or HTTP requests, including websites, APIs, login systems, and smart-contract interfaces.

In plain words
What is it for?
Use it for cross-site scripting, SQL injection, server-side template injection, server-side request forgery, XML attacks, JWT or login bypasses, file uploads, request smuggling, OAuth/OIDC, SAML, and smart-contract frontends or backends.
Why use it?
It helps identify weaknesses in how a web target handles requests, templates, files, identity, or user input. This focuses the investigation on the parts of an HTTP application that are most relevant to the puzzle.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/curiouslearnerdev/online_tools-ai/ctf-web
Any agent
npx skills add CuriousLearnerDev/Online_Tools-AI --skill ctf-web
Clone the repo
git clone --depth 1 https://github.com/CuriousLearnerDev/Online_Tools-AI

Made for: Claude Code, Codex.

Per session 124 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,674 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 2 findings. Scan, not verified.
Origin unknown No closer match found 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 $0.00124 $0.02674
Opus 5 $0.00062 $0.01337
Sonnet 5 $0.00025 $0.00535
Haiku 4.5 $0.00012 $0.00267

Measured 2d ago against content hash 3fd4cafdb39b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

ctf-web scanned grade B with 2 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 2d 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.

Sends data to an external URLmediumData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

curl -v -X POST https://target.com/api -H "Content-Type: application/json" -d '{}'

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

apt install hashcat jq curl
storage/Skill/ctf-skills/ctf-web/SKILL.md · 153 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 2d ago First seen · 153 lines · 124 tokens per session scan B 3fd4cafdb39b

Subscribe to this mod's changes

ctf-web is a skill published in the GitHub repository CuriousLearnerDev/Online_Tools-AI (52 stars, last pushed 1mo ago), with no licence file. It adds 124 tokens to every session and 2,674 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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