unp 1.0.12, and other versions before 1.0.14, does not properly escape file names, which might allow context-dependent attackers to execute arbitrary commands via shell metacharacters in a filename argument. NOTE: this might only be a vulnerability when unp is invoked by a third party product.
http://www.securityfocus.com/bid/27182
http://security.gentoo.org/glsa/glsa-200801-01.xml
http://secunia.com/advisories/28388
http://secunia.com/advisories/28282