The cvsweb CGI script in CVSWeb 1.80 allows remote attackers with write access to a CVS repository to execute arbitrary commands via shell metacharacters.
https://exchange.xforce.ibmcloud.com/vulnerabilities/4925
http://www.turbolinux.com/pipermail/tl-security-announce/2000-August/000015.html
http://www.securityfocus.com/bid/1469
http://archives.neohapsis.com/archives/bugtraq/2000-07/0178.html