viralator CGI script in Viralator 0.9pre1 and earlier allows remote attackers to execute arbitrary code via a URL for a file being downloaded, which is insecurely passed to a call to wget.
https://exchange.xforce.ibmcloud.com/vulnerabilities/7440
https://euvd.enisa.europa.eu/vulnerability/EUVD-2001-0832
http://www.securityfocus.com/bid/3495