debsecan: 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/bin/debsecan - from package: debsecan

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

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