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 "/".
Improper Limitation of a Pathname to a Restricted Directory The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.