Hi All !!
While I was testing desktop based firewalls (here it is Zone Alarm Pro) with
the firewall evasion kit developed by me, I found that a very old flaw still
exists in many latest versions of desktop based firewalls. It is possible
for a malicious program to bypass a desktop based firewall by using DDE-IPC
(Direct Data Exchange - Interprocess Communications) which enables an
un-trusted program to communicate with the attacker or access internet via
other trusted programs (Ex: Internet Explorer). This flaw is known since
before year 2003.
As per a post by Te Smith (Sr. Director, Corporate Communications, Zone
Labs), this issue is resolved in higher version Zone Alarm Pro having
Advanced Program Control feature. (Ref #
http://seclists.org/lists/bugtraq/2003/Jul/0000.html) However, I find that
this issue still exists in higher versions of Zone Alarm Pro and might also
exist in other desktop based firewalls.
I didn't find any good PoC around, so I thought of writing a PoC which can
demonstrate and explain how an un-trusted program can access internet or
establish connection with the attacker via other trusted programs by
leveraging over the DDE-IPC design flaw.
The PoC can be downloaded from the following link:
Tr0y (aka Debasis Mohanty)