NetworkManager VPNC plugin: Privilege escalation

Background

NetworkManager is an universal network configuration daemon for laptops, desktops, servers and virtualization hosts.

The VPNC plugin provides easy access Cisco Concentrator based VPN’s utilizing NetworkManager.

Description

When initiating a VPNC connection, NetworkManager spawns a new vpnc process and passes the configuration via STDIN. By injecting a special character into a configuration parameter, an attacker can coerce NetworkManager to set the Password helper option to an attacker controlled executable file.

Impact

A local attacker is able to escalate privileges via a specially crafted configuration file.

Workaround

There is no known workaround at this time.

Resolution

All NetworkManager VPNC plugin users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose
 ">=net-misc/networkmanager-vpnc-1.2.6"