Python 2.6 through 3.2 creates ~/.pypirc with world-readable permissions before changing them after data has been written, which introduces a race condition that allows local users to obtain a username and password by reading this file.
Exploitability
AV:LAC:MAu:NImpact
C:PI:NA:N1.9/AV:L/AC:M/Au:N/C:P/I:N/A:N