The edit_textarea function in form-file.c in Netrik 1.15.4 and earlier does not properly verify temporary filenames when editing textarea fields, which allows attackers to execute arbitrary commands via shell metacharacters in the filename.
http://www.vupen.com/english/advisories/2006/5092
http://www.securityfocus.com/bid/22158
http://www.debian.org/security/2007/dsa-1251
http://sourceforge.net/project/shownotes.php?release_id=472131&group_id=23183
http://secunia.com/advisories/23822
http://netrik.cvs.sourceforge.net/netrik/netrik/form-file.c?r1=1.3&r2=1.4