RubyGems is vulnerable to a denial of service (DoS) attack. It is possible due to a flaw in Gem::Version::VERSION_PATTERN in lib/rubygems/version.rb which allows a malicious gem version to cause a large amount of backtracking in a regular expression.
blog.rubygems.org/2013/09/09/CVE-2013-4287.html
blog.rubygems.org/2013/09/09/CVE-2013-4287.html
rhn.redhat.com/errata/RHSA-2013-1427.html
rhn.redhat.com/errata/RHSA-2013-1427.html
rhn.redhat.com/errata/RHSA-2013-1441.html
rhn.redhat.com/errata/RHSA-2013-1441.html
rhn.redhat.com/errata/RHSA-2013-1523.html
rhn.redhat.com/errata/RHSA-2013-1523.html
rhn.redhat.com/errata/RHSA-2013-1852.html
rhn.redhat.com/errata/RHSA-2013-1852.html
rhn.redhat.com/errata/RHSA-2014-0207.html
rhn.redhat.com/errata/RHSA-2014-0207.html
secunia.com/advisories/55381
secunia.com/advisories/55381
www.openwall.com/lists/oss-security/2013/09/10/1
www.openwall.com/lists/oss-security/2013/09/10/1
access.redhat.com/security/updates/classification/#moderate
puppet.com/security/cve/cve-2013-4287
puppet.com/security/cve/cve-2013-4287
rhn.redhat.com/errata/RHSA-2014-0207.html