Possible bug: SSH doesn't prefer host keys listed in SSHFP records while connecting.

Yegor Ievlev koops1997 at gmail.com
Sat Feb 23 22:30:34 AEDT 2019

The reason why this is a bug is, for example, that if the server was
updated and it re-generated the ECDSA key you deleted, you would have
to do some non-obvious steps for your client to ignore it.

On Sat, Feb 23, 2019 at 11:49 AM Damien Miller <djm at mindrot.org> wrote:
> On Fri, 22 Feb 2019, Yegor Ievlev wrote:
> > Steps to reproduce:
> > 1. Run a SSH server with default configuration and point a domain to it.
> > 2. Add SSHFP record to the domain, but only for Ed25519 key.
> > 3. Attempt to connect with VerifyHostKeyDNS set to yes, but the rest
> > of settings set to defaults.
> > 4. OpenSSH defaults to ECDSA instead of Ed25519 and refuses connection
> > because there is no ECDSA fingerprint in SSHFP records.
> I'm not seeing the bug: typically you'd add SSHFP records for all
> the server's hostkeys, but you've not done this.
> -d

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