JWT Token Attack

JWT Token Attack is a Quality skill for Claude Code, published by CyberStrikeus in CyberStrike.

1.7K stars269 forkson CyberStrikeus/CyberStrikeAdded 2026/08/12+4% in starsRepository updated 2026/08/12

aiai-agentai-securitybug-bountycybersecuritydevsecopsethical-hackinghackinghacking-toolllmmcpmcp-servermitre-attackoffensive-securityowasppenetration-testingpentestred-teamsecuritysecurity-tools

Install in seconds

Install JWT Token Attack

Copy JWT Token Attack into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/CyberStrikeus/CyberStrike/tree/main/.cyberstrike/skill/attack-jwt ~/.claude/skills/attack-jwt

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/CyberStrikeus/CyberStrike.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: .cyberstrike/skill/attack-jwt/SKILL.md in CyberStrikeus/CyberStrike
Installs to: ~/.claude/skills/attack-jwt
Collection: One of 51 skills cataloged from this repository
Category: Quality — 1354 skills

What JWT Token Attack does

JWT Token Attack tests JWT implementations for alg=none bypass, key confusion, claim tampering, and kid injection. Use it when checking whether a service accepts forged or modified tokens.

JWT Token Attack is cataloged under Quality on DirSkills. JWT Token Attack comes from a repository tagged ai, ai-agent, ai-security, bug-bounty and cybersecurity.

Documentation

README

Excerpt

# Automated JWT analysis and tamper token generation
attack_script jwt_tamper EYTOKEN --json-output

# Manual decode
echo "HEADER.PAYLOAD.SIG" | cut -d. -f1 | base64 -d 2>/dev/null
echo "HEADER.PAYLOAD.SIG" | cut -d. -f2 | base64 -d 2>/dev/null

Check for:

Algorithm (alg field): RS256, HS256, none
Claims: role, is_admin, sub, exp, aud, iss
Key ID (kid): SQL injection, path traversal potential

Phase 2: Algorithm Attacks

This is the opening of the README. Read the full README on GitHub.

Frequently asked about JWT Token Attack

What else does CyberStrikeus publish alongside JWT Token Attack?
JWT Token Attack is one of 51 skills that DirSkills catalogs from CyberStrikeus/CyberStrike, the repository it ships in. Its siblings there include AMI Age Compliance, AMI Encryption Check and AMI Naming Convention Compliance. Each one is a separate skill with its own page in this directory, installs the same way JWT Token Attack does, and is maintained by CyberStrikeus in that same repository. The rest of the collection is listed on the CyberStrikeus/CyberStrike page.
How does JWT Token Attack compare to other Quality skills?
JWT Token Attack ranks #603 by stars among the 1354 Quality skills in this catalog. The most-starred ones next to it are Benchmark, Benchmark Optimization Loop and API Design Patterns. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of JWT Token Attack against them. Open each page to compare what they document and how they install.