any ssh command returns error: ssh_depotgis_xmpp_abilan : command not found

Question

I am on Ubuntu 22.04.3, and I am trying to connect to an ssh bastion. But any command starting with ssh (such as ssh -V) returns an error for which I cannot find any documentation:

ssh_depotgis_xmpp_abilan : command not found

I have tried updating/upgrading openssh-client ('sudo apt upgrade openssh-client', already up-to-date) and all packages (sudo apt update && sudo apt upgrade -y), nothing changed.

Answers to comments/suggestions:

• Nothing related in .bashrc or .bash_aliases, or in the result from the command alias.

• which ssh and ls -l "$(which ssh)" both return /usr/bin/ssh

• The command /usr/bin/ssh -V returns:

OpenSSH_8.9p1 Ubuntu-3ubuntu0.6, OpenSSL 3.0.2 15 Mar 2022

but ssh -V returns the error message ssh_depotgis_xmpp_abilan : command not found

• using bash, hash -rdoes not return anything