JSON Web Tokens (JWTs) are widely used for authentication and authorisation in modern applications. Common vulnerabilities include: algorithm confusion attacks (accepting 'none' algorithm or switching from RSA to HMAC), weak signing keys (brute-forceable HMAC secrets), missing expiration enforcement, insufficient claim validation, token replay attacks, and sensitive data in unencrypted JWT payloads. Testing evaluates the complete token lifecycle from issuance through validation to revocation.
Technical2026-11-28
JWT Token Security Testing: Common Vulnerabilities in JSON Web Tokens cho Doanh nghiệp Việt Nam
JWTs power modern authentication but common implementation flaws can lead to authentication bypass and privilege escalation. Guidance for VN market.