There are two vulnerabilities in FW-1. The first is an authentication issue, the other is a configuration issue. Since I don't have a copy of 4.x FW-1 handy maybe someone can check it for me. #1 The basic authentication used in Checkpoint FW-1 used for inside/outbound and outside/inbound allows unlimited attempts to authenticate without a timeout or disconnect between unsuccessful attempts. To make matters worse, the attempt at authentication will let you know if you have the wrong username before you are allowed to enter in the passsword. The exploit is trivial, grind away at user names until you hit one that works and then grind away at passwords with the username you just found until you find one that works. For an example of this, set authentication on the FW-1 software to authenticate telnet connections. Telent to a destination past the firewall, when prompted for a username, pound away. A script could crack the authentication in a very short time. The workaround is to use Checkpoint's encrypted authentication program "SecuRemote" and not allow clear text authentication (browser based, telnet, etc.) to destinations beyond the firewall. #2 The default configuration in FW-1 allows for rlogin management of the server. The rlogin prompt is avaialable on all NICs. Unless a rule is placed in your ruleset to drop or reject all connections to the firewall, the authentication problem above can be used to remotely administer someone elses firewall without them knowing. The workaround is to include the rule.
This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 15:29:40 PDT