oscap-vm: command not found

Have You tried accessing the binary with the full path?

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 CentOS possible default full paths are:

/usr/bin/oscap-vm - from package: openscap-utils

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