L14 · IDENTITY AND TRUST
Sign it, then break it
Sign a message, submit it, then change one character and submit it again.
Planned
Steps
Sign a message with your key and submit it.
What the server will check: The server verified the signature.
Change one character in the message and submit it again with the same signature.
What the server will check: The server rejected it for the same key.
A signature covers every byte. Any change, however small, breaks it.
When it opens
This lab is planned. It opens when these are in place:
- A lab challenge endpoint
A lab endpoint records what it receives for your attempt and grades it on the server.