yhsm-yubikey-ksm: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/sbin/yhsm-yubikey-ksm - from package: yhsm-yubikey-ksm

You may install the required package with command apt-get install {package}

Error in other languages:
yhsm-yubikey-ksm: bevel nie gevind nie
yhsm-yubikey-ksm: comandă negăsită
yhsm-yubikey-ksm: comando não encontrado
yhsm-yubikey-ksm: commande introuvable
yhsm-yubikey-ksm: command not found
yhsm-yubikey-ksm: käsku ei ole
yhsm-yubikey-ksm: không tìm thấy lệnh
yhsm-yubikey-ksm: komanda nerasta
yhsm-yubikey-ksm: Kommando nicht gefunden.
yhsm-yubikey-ksm: kommandot finns inte
yhsm-yubikey-ksm: komut yok
yhsm-yubikey-ksm: nie znaleziono polecenia
yhsm-yubikey-ksm: níor aimsíodh an t-ordú
yhsm-yubikey-ksm: no se encontró la orden
yhsm-yubikey-ksm: no s'ha trobat l'ordre
yhsm-yubikey-ksm: opdracht niet gevonden
yhsm-yubikey-ksm: parancs nem található
yhsm-yubikey-ksm: perintah tidak ditemukan
yhsm-yubikey-ksm: príkaz nenájdený
yhsm-yubikey-ksm: příkaz nenalezen
yhsm-yubikey-ksm: команда не найдена
yhsm-yubikey-ksm: командата не е открита
yhsm-yubikey-ksm: 命令找不到
yhsm-yubikey-ksm: コマンドが見つかりません