The line printer daemon (lpd) in the lpr package in multiple Linux operating systems allows local users to gain root privileges by causing sendmail to execute with arbitrary command line arguments, as demonstrated using the -C option to specify a configuration file.
https://exchange.xforce.ibmcloud.com/vulnerabilities/3841
http://www.securityfocus.com/bid/927
http://www.redhat.com/support/errata/RHSA-2000-002.html
http://www.l0pht.com/advisories/lpd_advisory
http://www.kb.cert.org/vuls/id/39001
http://www.debian.org/security/2000/20000109
http://www.atstake.com/research/advisories/2000/lpd_advisory.txt