Secunia Security Advisory – Debian has issued an update for usermin. This fixes a vulnerability, which can be exploited by malicious users to cause a DoS (Denial of Service).
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/50129/sa21981.txt
Source: https://packetstormsecurity.com/files/50129/Secunia-Security-Advisory-21981.html