phion netfence / Barracuda NG Firewall: Remote Command Execution with root Privileges

Security Advisory
Vulnerable Software: Barracuda NG Firewall / phion netfence
Found by: Wolfgang Neudorfer, Lukas Nothdurfter
Impact: Remote Command Execution with root Privileges
Severity: Critical

Product Description
The Barracuda NG Firewall is a family of hardware and virtual appliances designed to protect network infrastructure, improve site-to-site connectivity and simplify administration of network operations. Beyond its powerful network firewall, IPS and VPN technologies, the Barracuda NG Firewall integrates a comprehensive set of next generation firewall technologies, including Layer 7 application control, WAN optimization, Web filtering, anti-virus, anti-spam and network access control enforcement.


Vulnerability Description
It is possible to execute an arbitrary command with root privileges on phion netfence 4.0.x, phion netfence < 4.2.15 and NG Firewall < 5.0.2 boxes with activated external authentication scheme (i.e. Active Directory). An attacker with the knowledge of an admin's username is able to perform arbitrary shell commands during the ssh login procedure on the box. The knowledge of the admin's password is not required.

A proof-of-concept exploit will not be disclosed due to a responsible disclosure agreement with the vendor.

Because of the high impact and the broad range of vulnerable versions, the severity is considered to be critical.

Vulnerable Versions
phion netfence 4.0.x
phion netfence < 4.2.15
NG Firewall < 5.0.2

Hotfix 392_Authentication for netfence 4.0.x
Hotfix 390_Authentication for netfence 4.2.x
Hotfix 391_Authentication for NG Firewall 5.0.x

Contact Timeline
2011-03-14: Vendor informed
2011-03-15: Hotfixes available for download
2011-06-11: Responsible disclosure