linux – 为什么vsftpd的chroot_local_user不安全？

我正在设置我的VPS和vsftpd,我不希望用户被允许离开他们的ftp主目录.我正在使用local_user ftp,而不是匿名,所以我补充说：

chroot_local_user=YES

我在很多论坛帖子中都读过,这是不安全的.

>为什么这不安全？
>如果因为使用ssh加入我的VPS而不安全,那么我可以从sshd锁定这些用户,对吧？
>是否还有其他选择来实现vsftpd的这种行为？ (我不想删除我系统上“world”的所有文件夹/文件的读取权限)

解决方法

点击这里查看 VSFTPD’s FAQ以获得您想要的答案.以下是我认为将回答您的问题的重要摘录.

Q) Help! What are the security implications referred to in the
“chroot_local_user” option?

A) Firstly note that other ftp daemons have the same implications. It is a generic problem. The problem isn’t too severe,but it is this: Some people have FTP user accounts which are not trusted to have full shell access. If these accounts can also upload files,there is a small risk. A bad user Now has control of the filesystem root,which is their home directory. The ftp daemon might cause some config file to be read – e.g. /etc/some_file. With chroot(),this file is Now under the control of the user. vsftpd is careful in this area. But,the system’s libc might want to open locale config files or other settings…

原文地址：https://www.jb51.cc/linux/402264.html