xsec-cipher: 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 Debian possible default full paths are:

/usr/bin/xsec-cipher - from package: xml-security-c-utils

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