The change_user method in the SUIDManager (lib/puppet/util/suidmanager.rb) in Puppet 2.6.x before 2.6.14 and 2.7.x before 2.7.11, and Puppet Enterprise (PE) Users 1.0, 1.1, 1.2.x, 2.0.x before 2.0.3 does not properly manage group privileges, which allows local users to gain privileges via vectors related to (1) the change_user not dropping supplementary groups in certain conditions, (2) changes to the eguid without associated changes to the egid, or (3) the addition of the real gid to supplementary groups.
exchange.xforce.ibmcloud.com/vulnerabilities/73445
github.com/puppetlabs/puppet/commit/76d0749f0a9a496b70e7dc7e6d6d6ff692224e36
nvd.nist.gov/vuln/detail/CVE-2012-1053
ubuntu.com/usn/usn-1372-1
web.archive.org/web/20120504011717/puppetlabs.com/security/cve/cve-2012-1053
web.archive.org/web/20120513215447/projects.puppetlabs.com/issues/12458
web.archive.org/web/20120513215653/projects.puppetlabs.com/issues/12457
web.archive.org/web/20120513223437/projects.puppetlabs.com/issues/12459
web.archive.org/web/20120527071855/www.securityfocus.com/bid/52158
web.archive.org/web/20120816020421/projects.puppetlabs.com/projects/1/wiki/Release_Notes#2.6.14
www.debian.org/security/2012/dsa-2419