Agent skill · Security

offensive-jwt

JWT attack methodology for penetration testers. Covers algorithm confusion (alg:none, RS256→HS256), weak HMAC secret brute force, kid parameter injection (SQLi, path traversal), jku/x5u/jwk header injection, JWKS cache poisoning, JWS/JWE confusion, timing attacks, and mobile JWT storage extraction. Use when testing JWT-based authentication, hunting auth bypass via token manipulation, or evaluating JWT implementation security in web or mobile apps.

SnailSploitgithub.com/SnailSploitGitHub ↗
claude-codeMIT
Install
npx skills add SnailSploit/Claude-Red --skill offensive-jwt --agent claude-code

Same command for any agent — swap --agent for codex, cursor, copilot.

Facts
Files in the skill folder: 1
SKILL.md size: 10 KB
Bundled scripts: none
Path: Skills/auth/offensive-jwt/SKILL.md
Open the folder on GitHub →
Where it comes from
Stars: 2,808
Language: Python
Read our review of the source →

Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.

From the SKILL.md

## Overview Comprehensive JWT attack checklist for offensive security engagements. Follow steps in order; apply each technique to the current target context and track which items have been completed. ## Quick Reference: Misconfigurations to Check - Algorithm set to `none` — signature verification bypassed entirely - Algorithm switching between `RSA` and `HMAC` (confusion attack) - Weak or guessabl

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About this skill
What does the offensive-jwt skill do?

JWT attack methodology for penetration testers. Covers algorithm confusion (alg:none, RS256→HS256), weak HMAC secret brute force, kid parameter injection (SQLi, path traversal), jku/x5u/jwk header injection, JWKS cache poisoning, JWS/JWE confusion, timing attacks, and mobile JWT storage extraction. Use when testing JWT-based authentication, hunting auth bypass via token manipulation, or evaluating JWT implementation security in web or mobile apps.

How do I install it?

Run `npx skills add SnailSploit/Claude-Red --skill offensive-jwt --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.

Where does this skill come from?

From SnailSploit/Claude-Red, a repository with 2,808 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.

Is a popular skill a good skill?

Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.

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