To increase the security of an NFS (Network File System) client mount point on a web server, you can use the noexec, nosuid, and nodev mount options.
The noexec option prevents the execution of any binaries from the mounted file system. This can be useful in preventing attackers from uploading and executing malicious code on the web server.
The nosuid option prevents the execution of any setuid or setgid binaries from the mounted file system. Setuid and setgid are Unix permissions that allow a program to be executed with the permissions of the owner or group owner of the file, rather than the permissions of the user running the program. This can be useful in preventing attackers from using setuid/setgid programs to escalate their privileges on the web server.
The nodev option prevents the access to device special files on the mounted file system. This can be useful in preventing attackers from accessing device files and potentially causing unintended behavior or system damage.
To use these options, you can specify them as part of the mount command when mounting the NFS file system. For example:
mount -o noexec,nosuid,nodev nfs_server:/path/to/nfs/share /local/mount/point
It's important to note that these options may not be suitable for all environments and may impact the functionality of your web server. It's always a good idea to carefully consider the security implications and potential impact on your system before using any security options.