Invision Power Board (IPB) 1.0 through 2.0.4 allows non-root admins to add themselves or other users to the root admin group via the "Move users in this group to" screen.
AV:L/AC:L/Au:N/C:P/I:P/A:P
This vulnerability has a 0.50% probability of being exploited in the next 30 days, ranking higher than 40% of all scored CVEs.