I have been having the same problem for weeks. I called
DVC and they sent me the following e-mail on June 24th.
"Thank you for contacting Member Services.
The error message on dvcmember.com has been brought to the attention of
our IT Partners. They are working on identifying the cause so that they
can correct the issue. Please note that this is not a security concern,
however it is an IT error that is being worked on.
We do appreciate your concern and your continued patience as we hope to
have this resolved soon.
Thank you again for your message
Member Services | Online Communications
Disney Vacation Club"
I have not heard from them since. But at least they say it is not a security concern.