SSH Agent / Selecting 'Require user confirmation when this key is used' causes failed ssh login attempt

[rolling-thundar]

Overview

Steps to Reproduce

1. Create a new key
   ssh-keygen -t ed25519 -a 100
2. Add the generated private key to keepassxc as attachment
3. Add the chosen password into the 'Password' field
4. Deselect these options:

• 'Add key to agent when database is opened/unlocked'
• 'Remove key from agent when database is closed/locked'

5. [IMPORTANT] Select the option 'Require user confirmation when this key is used'
   --> this is the option causing trouble
6. Save the entry
7. Add key to SSH agent
8. Go to terminal and try to ssh into your server:
   $ssh user@server

Expected Behavior

A pop-up message asking me whether I want to login with this key to my server.

Once I click on 'Ok', I successfully connect to my server.

Actual Behavior

I don't see the prompt message. Instead I get the following error message:

$ssh user@server
sign_and_send_pubkey: signing failed for ED25519 "user@client" from agent: agent refused operation
user@server: Permission denied (publickey).

Context

This problem only appears with the following SSH agent settings selected:

'Require user confirmation when this key is used'

As soon as I deselect the option, I can successfully ssh into my server.

KeePassXC - 2.7.6
Revision: dd21def

Operating System: Linux (Pop_OS)
Desktop Env: Regolith Desktop (3.0)
Windowing System: X11

[rolling-thundar]

The same behaviour happens when I login to Pop_OS with the default Gnome Desktop Env, instead of Regolith Desktop.

[droidmonkey]

This is on your ssh agent, if it doesn't support the setting then it generally fails to accept the key from us. Just disable the setting or use an ssh agent that supports this feature.

[rolling-thundar]

Gotcha. Thanks for the quick response.