Certain vulnerabilities in Python and Java have been detected and they can help crooks defeat firewalls that computer owners might have built to protect themselves. Bugs that are present in Java could interfere with FTP completion and initiate commands. Alexander Klink was the one that discovered a truth about Java not properly reviewing syntax of user name which is used to enter a server. Java-based systems support FTP and when its server is attempted to be connected, a certain validation is required. While this sound good, the verification implemented is the process that carries bugs. Since the syntax of usernames is not checked, long story short, hackers can assign novel commands. As Klink summarized, due to this vulnerability, crooks could potentially connect to a malicious server from the device they are attempting to influence. Another concern is described as the fact that such activity could also allow crooks to obviate firewalls.
A very much alike bug was detected in a couple of Python libraries. If user does not operate with Java, a similar invasion could take place thanks to it. However, the bug in Python is not as powerful and would be restricted to cause disorder via directory names specified in the URL.
Bugs in FTP control channel permits hackers to gain control over the commands initiated by FTP users. Then, a vile PORT command is supposed to be inserted once the window of opportunity opens. Once the firewall receives a command, it will take the internal IP address and port command to transform them into an external variant. After that, not a permanent NAT rule will be drawn for the sake of TCP kicking in. Imagine that hackers replace the IP address with another server which then results in a firewall being tricked into opening up a port. Of course, if crooks attempt to pull this invasion off, they are to be aware of the internal IP address of the user they wish to attack.
Tips for prevention and protection for your firewall
Since Java seems to be the mother of all problems, you should consider getting rid of it from all your devices. There might be times when such an option is not available to some users. In that case, we would simply recommend them to turn off Java browser plugin from all applications for browsing.
In addition to that, you could make modifications to your firewall. You are to select passive mode instead of classic one.
Lastly, you can think of demanding an update for your applications from the companies that develop the bugged software.
Source: networkworld.com.
