python -- buffer overrun in repr() for unicode strings

Benjamin C. Wiley Sittler reports:

I discovered a [buffer overrun in repr() for unicode
strings]. This causes an unpatched non-debug wide
(UTF-32/UCS-4) build of python to abort.

Ubuntu security team reports:

If an application uses repr() on arbitrary untrusted data,
this [bug] could be exploited to execute arbitrary code
with the privileges of the python application.