4 ms·

But.. public keys are public? Its not sending your private keys to anyone.

• jasonjayr 5y ago
  Right; but with agent forwarding, an 'evil' process on the target machine, that has privileges to connect to your agent socket (ie, root, or another pid as uid), can ask your agent to sign anything. Your key doesn't get exposed, but the agent will cheerfully sign requests no matter where they are going or where they came from. So, say a virus, or a worm or something just went through your ~/.ssh/config file, your ~/.bash_history and/or your ~/.ssh/known_hosts (if you arn't using host name hashing) -- they could attempt to connect to all your previous hosts with your agent connection, and usually the agent won't offer any clue that this is ongoing ...