The (1) ftpd and (2) ksu programs in (a) MIT Kerberos 5 (krb5) up to 1.5, and 1.4.x before 1.4.4, and (b) Heimdal 0.7.2 and earlier, do not check return codes for setuid calls, which might allow local users to gain privileges by causing setuid to fail to drop privileges. NOTE: as of 20060808, it is not known whether an exploitable attack scenario exists for these issues.
http://www.vupen.com/english/advisories/2006/3225
http://www.ubuntu.com/usn/usn-334-1
http://www.securityfocus.com/bid/19427
http://www.securityfocus.com/archive/1/443498/100/100/threaded
http://www.securityfocus.com/archive/1/442599/100/0/threaded
http://www.pdc.kth.se/heimdal/advisory/2006-08-08/
http://www.novell.com/linux/security/advisories/2006_20_sr.html
http://www.kb.cert.org/vuls/id/401660
http://www.gentoo.org/security/en/glsa/glsa-200608-15.xml
http://www.debian.org/security/2006/dsa-1146
http://web.mit.edu/Kerberos/advisories/MITKRB5-SA-2006-001-setuid.txt
http://securitytracker.com/id?1016664
http://security.gentoo.org/glsa/glsa-200608-21.xml
http://secunia.com/advisories/23707
http://secunia.com/advisories/21613
http://secunia.com/advisories/21527
http://secunia.com/advisories/21467
http://secunia.com/advisories/21461
http://secunia.com/advisories/21439
http://secunia.com/advisories/21436