Usermin before 1.220 (20060629) allows remote attackers to read arbitrary files, possibly related to chfn/save.cgi not properly handling an empty shell parameter, which results in changing root's shell instead of the shell of a specified user.
https://exchange.xforce.ibmcloud.com/vulnerabilities/29010
http://www.webmin.com/uchanges.html
http://www.vupen.com/english/advisories/2006/3668
http://www.securityfocus.com/bid/18574
http://www.osreviews.net/reviews/admin/usermin
http://www.debian.org/security/2006/dsa-1177
http://sourceforge.net/tracker/index.php?func=detail&aid=1509145&group_id=17457&atid=485894