Incomplete blacklist vulnerability in sudo 1.6.8 and earlier allows local users to gain privileges via the (1) SHELLOPTS and (2) PS4 environment variables before executing a bash script on behalf of another user, which are not cleared even though other variables are.
http://www.vupen.com/english/advisories/2007/0930
http://www.us-cert.gov/cas/techalerts/TA07-072A.html
http://www.sudo.ws/bugs/show_bug.cgi?id=182
http://www.securityfocus.com/advisories/9643
http://www.openpkg.org/security/OpenPKG-SA-2006.002-sudo.html
http://www.novell.com/linux/security/advisories/2006_02_sr.html
http://www.mandriva.com/security/advisories?name=MDKSA-2005:201
http://www.debian.org/security/2005/dsa-870
http://secunia.com/advisories/24479
http://secunia.com/advisories/18549
http://secunia.com/advisories/17666
http://secunia.com/advisories/17390
http://secunia.com/advisories/17345
http://secunia.com/advisories/17322
http://secunia.com/advisories/17318
http://lists.apple.com/archives/security-announce/2007/Mar/msg00002.html