Using the Ubuntu 12.04 64-bit installation ISO image, downloaded from ubuntu.com on 8th May 2013, entering network configuration manually, enter blank default gateway - error message not allowing progress until valid default gateway is entered.
The description text for default gateway specifically states it can be left blank and the network I am installing on is completely isolated, hence has no default gateway.
Workaround is to enter a valid IP address for default gateway.
I am classing as a security vulnerability because you are forced to enter a gateway but a site security policy may require a machine is configured without a gateway to reduce risk of access to other (routable) networks. If a installation engineer believe a valid gateway is the only way to install the OS they may be tempted to enter it (rather than another IP address).
Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https:/
To change the source package that this bug is filed about visit https:/
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