It was found  that the fix for improved shell quoting to guard against shell injection, released in version 0.3.5  of python-gnupg, is not sufficient.
This issue has been reported upstream .
Created python-gnupg tracking bugs for this issue:
Affects: fedora-all [bug 1061600]
updates pushed to updates-testing for f19,f20,el6 (and built in rawhide)
This was assigned multiple CVE numbers:
CVE-2013-7323 Unrestricted use of unquoted strings in a shell,
within version 0.3.4
CVE-2014-1927 Erroneous assumptions about the usability of "
characters within version 0.3.5, leading to attacks
such as $( command substitution within a "-quoted
CVE-2014-1928 Erroneous insertion of a \ character within version
0.3.5, leading to attacks involving command lists
(such as lists separated by a ; character)
Full details: http://seclists.org/oss-sec/2014/q1/294
CVE-2014-1929 was assigned to:
Second, 0.3.5 and 0.3.6 have a series of differences in handling of
command-line arguments. This seems to be most likely a reaction to
Florian Weimer's observation of "you need to make sure that you
prevent option injection through positional arguments." Does anyone
believe that option injection was impossible in 0.3.5? If not, we will
make a fourth CVE assignment.