How come the PQC algos don't show up in the ssh -Q lists

[Darren Tucker]

On Mon, 27 Jul 2026 at 04:44, Roger Grimes via openssh-unix-dev
<openssh-unix-dev at mindrot.org> wrote:
> It's my understanding that at least 2-3 of the PQC algorithms (MLKEM768X25519-SHA256,

added in OpenSSH 9.9 (note that all of the names are lower case):
https://www.openssh.org/txt/release-9.9

>  SNTRUP761X25519-SHA512,

added in OpenSSH 8.9 (as a vendor extension) and 9.9 (with the
standardized name).
https://www.openssh.org/txt/release-8.9

> ML-DSA + Ed25519) are available in OpenSSH now.

That's ssh-mldsa44-ed25519 at openssh.com and was added in 10.4:
https://www.openssh.org/txt/release-10.4

> But when I run ssh -Q kex or -Q key I don't see them listed.
> Should they be listed?

Which OpenSSH version is this and/or which vendor supplied it?
Exactly what is available varies by OpenSSH version, see
https://www.openssh.org/specs.html for a summary.

-- 
Darren Tucker (dtucker at dtucker.net)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.