[Post-Install] Ssh-add -L just hangs after Kubuntu 25.10 upgrade from 25.04

[mcarans]

Since upgrading from 25.04 to 25.10, using ssh with GitHub has stopped working. ssh-add -L just hangs.

Should ksshaskpass or kwalletaskpass be the default ssh-askpass in Kubuntu 25.10 / Plasma 6.4.5?

I see:

> update-alternatives --config ssh-askpass
There are 2 choices for the alternative ssh-askpass (providing /usr/bin/ssh-askpass).

Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/bin/ksshaskpass 35 auto mode
1 /usr/bin/ksshaskpass 35 manual mode
2 /usr/bin/kwalletaskpass 30 manual mode

I want to check that is correct.

It seems like it cannot open the password dialog:

> ssh-add -v ~/.ssh/id_rsa
debug1: read_passphrase: requested to askpass

Running ksshaskpass does however show a password prompt.

Killing the agent and starting another works:

pkill ssh-agent
eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_rsa

I have run into problems with ssh after Kubuntu upgrades multiple times in the past. Nearly 3 years ago, I asked this How do I set up KDE, KWallet and ssh so I’m not asked to enter my ssh passphrase? on Unix&Linux Exchange, and answered my own question with a ksshaskpass setup that worked with Kubuntu 22.10.

Later when I upgraded to 24.04, the dialog changed from ksshaskpass to pinentry-qt and I had to make a setup with kwalletcli.

Now with 25.10 and Plasma 6.4.5, it seems that the default has changed back again to ksshaskpass after upgrade, but it’s not working properly (again).

I am now confused about what the default should be and how to make a working setup. Has anyone experienced this issue? Does anyone have a solution?

[mcarans]

It seems like SSH_AUTH_SOCK is not set correctly. It is /run/user/1000/openssh_agent in bash. I have added in ~/.bashrc: `export SSH_AUTH_SOCK="$XDG_RUNTIME_DIR/ssh-agent.socket"` which appears to fix the issue.