> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/web/jwt.md). # JWT Attacks JWT authentication bypass, algorithm confusion, weak keys, JWK injection, JKU injection, kid path traversal, and signature validation flaws. JWT Attacks notes for PortSwigger Web Security Academy labs, focused on practical testing steps, Burp Suite validation, payload behavior, and exploitation workflow. ## Testing Workflow 1. Identify the vulnerable feature and the relevant request, parameter, header, cookie, or browser-side sink. 2. Reproduce the behavior in Burp Suite with a minimal payload before escalating the attack. 3. Validate impact with a clear proof of concept, such as account access, data disclosure, code execution, SSRF, or state change. 4. Keep payloads, URLs, tokens, and lab credentials unchanged while documenting the exploitation path. ## Labs


JWT Authentication Bypass via Algorithm Confusion
JWT Authentication Bypass via Algorithm Confusion without Exposed Public Key
JWT Authentication Bypass via Flawed Signature Verification
JWT Authentication Bypass via JKU Parameter Injection
JWT Authentication Bypass via JWK Injection
JWT Authentication Bypass via kid Path Traversal
JWT Authentication Bypass via Unverified Signature
JWT Authentication Bypass with a Weak Key

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