severity of bug fixed with commit 180c09d

[twebb]

Can someone explain the severity of this bug?  It was fixed in
ubiformat.c in mid-January of this year.  I'm using ubiformat from
prior to this fix and do not see the problem that is described in the
commit log.  I'm trying to understand the bug in order to explain why
I'm not seeing the problem and to determine if I'm susceptible to the
bug.

Thanks,
twebb