NFS

ABOUT

Network File System (NFS) is a network file system developed by Sun Microsystems and has the same purpose as SMB. Its purpose is to access file systems over a network as if they were local. NFS is used between Linux and Unix systems. This means that NFS clients cannot communicate directly with SMB servers. The /etc/exports file contains a table of physical filesystems on an NFS server accessible by the clients.

Dangerous Settings

• rw - Read and write permissions.

• insecure - Ports above 1024 will be used.

• nohide - If another file system was mounted below an exported directory, this directory is exported by its own exports entry.

• no_root_squash - All files created by root are kept with the UID/GID 0.

Tips2Hack

1. Basic nmap footprinting

sudo nmap --script nfs* 13.13.13.13 -sV -p111,2049

1. Show available NFS shares

showmount -e 13.13.13.13

1. Mounting & Unmounting NFS shares

> mkdir target-NFS
> sudo mount -t nfs 13.13.13.13:/ ./target-NFS/ -o nolock
> sudo umount ./target-NFS

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