testing-jwt-token-security

name	testing-jwt-token-security
description	Assessing JSON Web Token implementations for cryptographic weaknesses, algorithm confusion attacks, and authorization bypass vulnerabilities during security engagements. Use when working with testing jwt token security.
domain	cybersecurity
tags	["penetration-testing","jwt","authentication","web-security","token-security","burpsuite"]
subdomain	web-application-security
version	1.0
author	oyi77
license	Apache-2.0
nist_csf	["PR.PS-01","ID.RA-01","PR.DS-10","DE.CM-01"]

Testing Jwt Token Security

Overview

Cybersecurity skill for testing jwt token security. Follows industry best practices and security standards.

When to Use

Trigger phrases:

• "testing jwt token security"

• "Assessing JSON Web Token implementations for cryptographic weaknesses, algorithm"

• During authorized penetration tests when the application uses JWT for authentication or authorization

• When assessing API security where JWTs are passed as Bearer tokens or in cookies

• For evaluating SSO implementations that use JWT/JWS/JWE tokens

• When testing OAuth 2.0 or OpenID Connect flows that issue JWTs

• During security audits of microservice architectures using JWT for inter-service authentication

When NOT to Use

• When you lack proper authorization for testing
• For production systems without change management
• When the task requires legal or compliance expertise beyond technical scope

Prerequisites

• Authorization: Written penetration testing agreement for the target
• jwt_tool: JWT attack toolkit (pip install jwt_tool or git clone https://github.com/ticarpi/jwt_tool.git)
• Burp Suite Professional: With JSON Web Token extension from BApp Store
• Python PyJWT: For scripting custom JWT attacks (pip install pyjwt)
• Hashcat: For brute-forcing HMAC secrets (apt install hashcat)
• jq: For JSON processing
• Target JWT: A valid JWT token from the application

Workflow

# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def () -> :
     {k: re.findall(v, text)  k, v  IOC_PATTERNS.items()}