Tests of Private Firewall 2

Key criteria in choosing a personnal firewall are :

• Effectiveness of security protection : penetration, Trojans, controlling leaks, denial of service.

• Effectiveness of intrusion detection: few false positives, alerting of dangerous attacks.

• User interface: ease of use, instructiveness, simplicity, quality of online help. Does the interface suit the way you use your PC ?

• Price.

How did we test firewall/intrusion detection effectiveness?

1. Ping and accessing shares to and from the test host.

2. A powerful, well known "remote control" Trojan (Netbus Pro v2.1 [2]) was installed on the system on a nonstandard port (to make detection more difficult), the Netbus server started and attempts made to connect from a remote system.

3. An nmap [1] scan was run, to check that incoming ports were effectively blocked. With another local PC launching nmaps againts the test PC and the following options (nmap -v -sT -P0 -O IP_ADDR).

4. An nmap [1] scan was run, to check that incoming ports were effectively blocked. With another local PC launching nmaps againts the test PC and the following options (nmap -v -sP -P0 -O IP_ADDR).

5. A test using Leaktest [4] was done.

6. We checked the system ressource usage of the firewall during the tests (just in case).

7. We tried to launch a modified (by us) release of IEXPLORE.EXE (C:\Program Files\Internet Explorer\IEXPLORE.EXE ) to check if the firewall detects the problem.

NB : These tests do not pretend to be exhaustives. By the way the aim is to be sure that the tested software offers at least expected security (or not) for a personnal use (do not compare this to professional use).

Jump to the test results.

The Private Firewall 2 firewall [3] is full of interesting features :

• Possibility to select type of use (home , office, mobility).

• Select one of 3 levels of filtering.

• Do a security report (built inside).

• Allow to customize the security rules.

• Download size : 6.2 MB

1. Ping: Impossible (in Normal mode). This is a good result.

2. The Netbus server: Private Firewall 2 does not detect the Netbus server when started, but it remains impossible to connect to the netbus server. The result of this test is good.

3. An nmap scan without Private Firewall 2 (on Win 2000 OS SP1 with a "standard" installation, it means NetBios active and so on) :
   
   $ nmap -v -sT -P0 -O IP_ADDR
   
   Starting nmap V. 2.53 by fyodor@insecure.org ( www.insecure.org/nmap/ )
   Initiating TCP connect() scan against (IP_ADDR)
   Adding TCP port 445 (state open).
   Adding TCP port 135 (state open).
   Adding TCP port 1025 (state open).
   Adding TCP port 913 (state open).
   Adding TCP port 139 (state open).
   
   The TCP connect scan took 0 seconds to scan 1523 ports.
   
   For OSScan assuming that port 135 is open and port 1 is closed and neither are firewalled
   
   Interesting ports on (IP_ADDR):
   (The 1518 ports scanned but not shown below are in state: closed)
   Port State Service
   135/tcp open loc-srv
   139/tcp open netbios-ssn
   445/tcp open microsoft-ds
   913/tcp open unknown
   1025/tcp open listen
   
   TCP Sequence Prediction: Class=random positive increments
   Difficulty=6634 (Worthy challenge)
   
   Sequence numbers: 747E9CE8 747F63FC 74800BF5 7480E3FE 7481BC4F 7482B3B2
   
   Remote operating system guess: Windows 2000 RC1 through final release
   
   Nmap run completed -- 1 IP address (1 host up) scanned in 10 seconds
   
   Gloups : you'd better have a firewall installed :+) !!!
   
   An nmap TCP scan with Private Firewall 2 (on Win 2000 SP1 OS with a "standard" installation, it means NetBios active and so on) with options security level Normal activated gives events registered in the logs which is a good result for detection :
   
   $ nmap -v -sT -P0 -O IP_ADDR
   
   Starting nmap V. 2.53 by fyodor@insecure.org ( www.insecure.org/nmap/ )
   Initiating TCP connect() scan against (IP_ADDR)
   The TCP connect scan took 1682 seconds to scan 1523 ports.
   Warning: No TCP ports found open on this machine, OS detection will be MUCH less reliable
   All 1523 scanned ports on (IP_ADDR) are: filtered
   Too many fingerprints match this host for me to give an accurate OS guess TCP/IP fingerprint:
   T5(Resp=N)
   T6(Resp=N)
   T7(Resp=N)
   PU(Resp=N)
   
   Nmap run completed -- 1 IP address (1 host up) scanned in 1870 seconds
   
   This means that with Private Firewall 2 active ports looks unexistant and access attempts are logged. This is a good result.
   

4. An nmap UDP scan with Private Firewall 2 (on Win 2000 SP1 OS with a "standard" installation, it means NetBios active and so on) gives events registered in the log which is a good result for detection and in this case the protection seems efficient :
   
   $ nmap -v -sU -P0 IP_ADDR
   
   Starting nmap V. 2.53 by fyodor@insecure.org ( www.insecure.org/nmap/ )
   Initiating FIN,NULL, UDP, or Xmas stealth scan against (IP_ADDR)
   The UDP or stealth FIN/NULL/XMAS scan took 90 seconds to scan 1448 ports.
   (no udp responses received -- assuming all ports filtered)
   All 1448 scanned ports on (IP_ADDR) are: filtered
   
   Nmap run completed -- 1 IP address (1 host up) scanned in 1755 seconds
   

   This means that the security seems good for UDP. This is a good result.

5. The Leaktest : Private Firewall 2 does not detect the launch of Leaktest but it's unable to connect. The result of this test is good.

6. Private Firewall 2 , in normal operations uses up to 10 % max of CPU. Memory usage is 5 MB, up to 6 MB peek.

7. The substitution test : (you can do it by yourself for example : you replace your ftp software with leaktest.exe - yes this one - by renaming the last one and launch it). The result is Private Firewall 2 allow the trojan horse to connect... the result of this test is bad.

1. Private Firewall 2 can be configured to block all trafic.

2. You can specified ports associated to an allowed application (it won't stop the substitution test, but it's nice).

3. Allow to export log in html format.

4. Allow to specify trusted IP.

5. Allow to do an internal system security checking (usefull).

1. Private Firewall 2 cannot really make any difference between local network connexions and Internet connexions.

2. No way to detect automatically a network software , you have to define them manually... one / one

• Improve the GUI (but keep it simple :) .

• Add network software detection.

• Product internationalization.

A good start and a nice tool, looks simple and efficient but some options are really missing.

Evaluation :

• Installation process (2) : 15/20

• Configuration , GUI (3) : 15/20

• Filtering security (5) : 15/20

• Additionnal security (3) : 10/20

• Software load and memory usage (2) : 15/20

• Import/Export configuration (2) : 0/20

• Help , FAQ (2) : 10/20

• Product internationalization (1) : 0/20

Total : 12.75 / 20

Note : the result may be modified with the release , and when adding new criteria or re-evaluating their weight or their content.

1. Nmap - Network mapper, a really efficient tool to check networks
   http://www.insecure.org/nmap

2. Netbus Pro - Remote control program often used as an attack tool to control remote PCs.
   http://www.netbus.org/
   download

3. Private Firewall 2 firewall
   http://www.privacyware.com

4. Leaktest - Small testing software written by Steve Gibson to check firewalls. It makes a simple TCP (ftp) connexion that simulate sennding of personnal content, which can also be used to take remote controle in reverse mode (arg).
   http://grc.com/
   download