The crash reporting feature in Apport 2.13 through 2.17.x before 2.17.1 allows local users to gain privileges via a crafted usr/share/apport/apport file in a namespace (container).
https://www.exploit-db.com/exploits/43971/
https://launchpad.net/apport/trunk/2.17.1
https://bugs.launchpad.net/ubuntu/%2Bsource/apport/%2Bbug/1438758