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2025-02-16
Method:
- Visit the specified URL: https://lnkd.in/dGcxDjFX
- Look for keywords such as
token=,key=,eyJ, etc. - URLs with parameters will often redirect to specific locations containing the JWT token directly.
- Decode the token using jwt.io.
Practice-Verified Commands:
To automate the discovery of JWT tokens in URLs, use the following command:
echo site.com | waybackurls | grep token= | httpx -mc -ct 200,302,301
This command fetches historical URLs from Wayback Machine, filters for tokens, and checks for live endpoints.
**What Undercode Say:**
JWT (JSON Web Token) vulnerabilities are a critical area in web application security. Misconfigured JWT tokens can lead to unauthorized access, data breaches, and privilege escalation. The command provided leverages `waybackurls` and `httpx` to identify exposed tokens, a common issue in bug bounty programs.
To further secure your systems, consider these additional commands and practices:
1. Validate JWT Signatures: Always verify the token signature to ensure it hasn’t been tampered with. Use libraries like `jsonwebtoken` in Node.js or `PyJWT` in Python.
2. Check Token Expiry: Ensure tokens have a short lifespan by setting an appropriate `exp` claim.
3. Use Strong Algorithms: Avoid using `none` as the signing algorithm. Prefer HMAC SHA-256 or RSA.
4. Monitor Logs: Use `grep` to search server logs for suspicious activity:
grep "eyJ" /var/log/nginx/access.log
5. Encrypt Sensitive Data: If tokens contain sensitive information, encrypt them using AES-256.
For further reading on JWT security, visit:
By combining automated tools with manual testing, you can effectively identify and mitigate JWT-related vulnerabilities. Always stay updated with the latest security practices and participate in bug bounty programs to sharpen your skills.
References:
Hackers Feeds, Undercode AI
