Piwik 0.2.32 and earlier stores sensitive information under the web root with insufficient access control, which allows remote attackers to obtain the API key and other sensitive information via a direct request for misc/cron/archive.sh.
http://www.openwall.com/lists/oss-security/2009/03/23/2
http://marco-ziesing.de/archives/35-Schluesselloch-in-Piwik.html