The (1) make_nonce, (2) generate_nonce, and (3) generate_verifier functions in SimpleGeo python-oauth2 uses weak random numbers to generate nonces, which makes it easier for remote attackers to guess the nonce via a brute force attack.
www.openwall.com/lists/oss-security/2013/09/12/7
www.securityfocus.com/bid/62388
access.redhat.com/errata/RHSA-2015:1591
access.redhat.com/errata/RHSA-2015:1592
access.redhat.com/security/cve/CVE-2013-4347
bugzilla.redhat.com/show_bug.cgi?id=1007758
github.com/joestump/python-oauth2
github.com/joestump/python-oauth2/commit/82dd2cdd4954cd7b8983d5d64c0dfd9072bf4650
github.com/simplegeo/python-oauth2/issues/9
github.com/simplegeo/python-oauth2/pull/146
nvd.nist.gov/vuln/detail/CVE-2013-4347