It was reported  that Python built-in _json module have a flaw
(insufficient bounds checking), which allows a local user to read
current process' arbitrary memory.
From initial bug report :
The sole prerequisites of this attack are that the attacker is able to
control or influence the two parameters of the default scanstring
function: the string to be decoded and the index.
The bug is caused by allowing the user to supply a negative index
value. The index value is then used directly as an index to an array
in the C code; internally the address of the array and its index are
added to each other in order to yield the address of the value that is
desired. However, by supplying a negative index value and adding this
to the address of the array, the processor's register value wraps
around and the calculated value will point to a position in memory
which isn't within the bounds of the supplied string, causing the
function to access other parts of the process memory.
 Upstream bug report with additional technical details: http://bugs.python.org/issue21529
 Debian bug tracker: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=752395
 RedHat bug tracker: https://bugzilla.redhat.com/show_bug.cgi?id=1112285
Upstream commits (taken from upstream tracker):
Created attachment 381670 [details, diff]
Thanks. Added to existing GLSA request.
This issue was resolved and addressed in
GLSA 201503-10 at https://security.gentoo.org/glsa/201503-10
by GLSA coordinator Kristian Fiskerstrand (K_F).