worth their weight in salt

大概看的出來這段話的意思是
"這不是個好主意,因為駭客可以透過已被侵入的電腦發動攻擊,而這些電腦真正的使用者卻不知情",但我看不太懂" worth their weight in salt "這部份,
(我上網查了一下,有個諺語叫"worth one's salt  "意思是"值得的",不知道有沒有關連??)

This is not a wise idea because any hackers worth their weight in salt lunch their attacks from computer systems that they have already compromised, and the true owner of the system is unaware of what is going on.