The original patch for a GNU tar directory traversal vulnerability (CVE-2002-0399) in Red Hat Enterprise Linux 3 and 2.1 uses an "incorrect optimization" that allows user-assisted attackers to overwrite arbitrary files via a crafted tar file, probably involving "/../" sequences with a leading "/".
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9946
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=140589
http://www.securityfocus.com/bid/5834
http://www.securityfocus.com/archive/1/430297/100/0/threaded
http://www.redhat.com/support/errata/RHSA-2006-0195.html
http://www.novell.com/linux/security/advisories/2006_05_sr.html
http://support.avaya.com/elmodocs2/security/ASA-2006-110.htm
http://securitytracker.com/id?1015655
http://secunia.com/advisories/20397
http://secunia.com/advisories/19183